
Apply the Pythagorean theorem to right triangles by using a^2 + b^2 = c^2 to find the hypotenuse or a leg, with practice problems illustrating solving for unknown sides.
Master geometry by practicing the Pythagorean theorem on right triangles, recognizing legs and the hypotenuse, and using Pythagorean triples to solve problems quickly. Learn how multiplying triples extends solutions.
Learn to classify triangles by angles—right, acute, obtuse—and by sides—scaling, isosceles, and equilateral (equal lateral). Triangles can fall into multiple categories.
Explore isosceles triangles, with two congruent sides and equal opposite angles. See how the altitude bisects the base and vertex angle, and apply this to proofs, including vertical angles.
Explore how interior angles of a triangle sum to 180 degrees, solve for unknown angles from two given angles or a ratio, and classify triangles as isosceles, scalene, or obtuse.
Master the 45-45-90 triangle by using the constant ratio x, x, x square root of two, and verify results with the Pythagorean theorem to solve for missing sides quickly.
Learn the 30-60-90 triangle, a special right triangle with fixed side ratios: shortest side opposite 30 degrees, longest leg x√3, and hypotenuse 2x, via the Pythagorean theorem.
Explore how the midsegment connects midpoints, stays parallel to the third side, and equals half its length, illustrated by a right triangle example with a 30 perimeter for DPF.
Learn to calculate triangle area with Heron's formula by finding the half perimeter s = (a+b+c)/2 and computing area = sqrt(s(s-a)(s-b)(s-c)).
Learn how to find arc length on circles by relating it to the circumference, using radius or diameter, and applying the arc length formula with practical, worked examples.
Explore how sector area represents the part of a circle enclosed by two radii and an arc, determined by the central angle, using the formula (angle/360) × πr^2.
Practice applying arc length and sector area formulas using central angle over 360 to scale circumference and area, with radii 9 and 8 and subtract triangle areas for remaining regions.
Explore chords, tangents, and secants in circles, noting that a diameter is a center-spanning chord equal to twice the radius, while tangents touch at one point and secants cross twice.
Explore the formulas for chords, tangents, and secants in circle geometry, including the intersecting chords formula, the secant-secant formula, and the tangent formula, with practical example explanations.
Practice problems apply the intersecting chords formula, secant form, and tangent form to find missing lengths by relating entire segments to their external parts.
Explore advanced chord, secant, and tangent problems using intersecting chords, secant-tangent, and tangent-secant formulas; practice solving for unknown lengths with quadratic steps and identification strategies.
Explore formulas for circle angles, including central angle equal to arc measure, inscribed angle equal to half the arc, and tangent and chord or intersecting chords scenarios.
Master circle area and circumference using radius or diameter, with A = pi r^2 and C = 2 pi r (or C = pi d), and practice solving for r.
Explore circles and their equations, convert general form to center-radius form by completing the square, and compute radius, diameter, circumference, and area.
Classify polygons by regular versus irregular, and convex versus concave, using angles and side lengths, with examples of quadrilaterals and parallelograms to illustrate.
Explore the interior angles of polygons, distinguishing regular and irregular shapes, and apply the 180(n-2) rule to find total and individual angles, with examples like octagons and hexagons.
discover how exterior angles of polygons sum to 360 degrees, distinguish regular from irregular polygons, and compute each exterior angle as 360/n and interior as 180-360/n.
Practice with interior and exterior angles of polygons, using the sums 180(n-2) and 360, and apply the exterior angle x relationship 180-x to find missing angles.
Master the midpoint of a segment by counting on a number line or by taking the mean of the x coordinates and the y coordinates.
Master the distance between two points using the distance formula, derived from the Pythagorean theorem, with coordinates x2 - x1 and y2 - y1.
Practice midpoint and distance formulas to find coordinates and segment lengths using the mean of coordinates and the Pythagorean theorem. Tackle challenging examples to reinforce the methods.
Learn how parallel lines share the same slope but have different y-intercepts, expressed in y = mx + b, and how to write a parallel line through a point.
Learn how to identify perpendicular lines, compute the slope as the negative reciprocal, convert to slope-intercept form, and write a perpendicular line through a given point.
Explore parallel and perpendicular lines by determining slopes and using negative reciprocals. Find line equations through given points and locate intersections.
Explore how a transversal intersects parallel lines to form angles that are congruent or supplementary, including alternate interior, alternate exterior, corresponding, and same-side interior angles.
Explore congruence, the idea that shapes have the exact same size and shape, even when rotated or slid, with a focus on corresponding sides, angles, and the order of letters.
learn the main triangle congruence methods, including side-side-side, side-angle-side, angle-side-angle, angle-angle-side, and hypotenuse-leg, and understand cpctc, the principle that corresponding parts stay congruent.
Practice recognizing congruent triangles using SSS, SAS (including the included side), ASA, AAS, and HL criteria, while identifying vertical angles and constructing proofs.
Apply reflexive and transitive properties, angle and segment bisectors, medians, and altitudes to triangle proofs. Use linear pair and parallel line theorems, plus corresponding parts of congruent triangles to conclude.
Master geometry basics with triangle congruence proofs, two-column proof techniques, reflexive property, and criteria such as side-angle-side, angle-side-angle, and vertical angles to prove triangles are congruent.
Master hard triangle congruence proofs through two-column proofs, using givens, segment bisectors, vertical angles, isosceles base angles, altitude right angles, and SAS, angle-angle-side reasoning, or the transitive property.
Explore similarity by defining the same shape with different sizes, recognizing corresponding angles equal and corresponding sides proportional, using triangle examples to illustrate ratios.
Explore numerical practice with similarity by examining proportional corresponding sides, angles, and the similarity symbol, and learn to solve for missing sides using side ratios.
Master geometry explains three methods for proving triangle similarity—angle-angle, side-side, and side-angle-side—where corresponding angles are equal and sides are proportional, not congruent.
Master geometry explains sphere surface area as the exterior measure, using the formula four pi r squared, derived from Archimedes’ work with a cylinder, with quick radius examples.
Master the volume of a sphere using the four thirds pi r cubed formula, and explore Archimedes’ two thirds relation to the cylinder to prepare for radius calculations.
Apply sphere surface area and volume formulas to solve questions, deriving radius from surface area and then computing volume, or vice versa, using pi r^2 and 4/3 pi r^3.
Explore cylinder surface area with the formula 2 pi r^2 + 2 pi r h, seeing how two bases and the side area compose the total.
Compute cylinder volume by multiplying base area pi r^2 by height, using the base area and height to solve ratio problems like radius to height and given volume 144 pi.
Practice solving cylinder volume and surface area problems, derive and apply formulas for volume and surface area, use diameter and circumference to find radius, and reinforce intuition with step-by-step reasoning.
Explore the surface area of a cube by treating it as six square faces and using the formula 6a^2 with edge length a.
Calculate the volume of a cube by applying the base area times height formula, using edge length examples and the concept that volume equals a cubed.
Practice applying cube volume and surface area formulas to find side length, volume, and surface area. Calculate with a=3, yielding volume 27 and surface area 54.
Explore the fundamentals of logic, including if P then Q, hypotheses, conclusions, and the four forms: converse, inverse, contrapositive, and their truth values in mathematical reasoning.
Explore keys to understanding logic in geometry: analyze contrapositive, converse, and inverse, compare truth values, apply to quadrilateral and square examples, and improve reasoning with practice.
Practice solving logical statements by identifying hypotheses and conclusions, judging truth values, and applying converse, inverse, and contrapositive through geometry examples such as rectangles with two pairs of parallel sides.
Learn the introduction to trigonometry for right triangles, mastering sine, cosine, and tangent ratios and the roles of opposite, adjacent, and hypotenuse, with reference angles and soh cah toa.
Learn to solve right triangles using soh cah toa, identify opposite, adjacent, and hypotenuse, and apply sine or cosine with inverse functions in degree mode to find sides and angles.
Apply the law of sines to solve triangles using the ratio sin A over a equals sin B over b equals sin C over c, with angles opposite sides.
Master the law of cosines to solve triangles using two sides and the included angle or all three sides, and apply the three equivalent formulas to find missing values.
Welcome to Master Geometry!
This is a brand new course designed to help you master the difficult topics of Geometry and get you prepared for your next math course, which may be trigonometry, advanced algebra, or precalculus. I have been tutoring for many years and my students have had great experiences with my teaching methods!
Here's what students of previous classes have had to say:
Freaking awesome instructor! this has taught me a lot. - Zacchary, Udemy Student
This was an excellent course. Each topic is well explained. The intimidation of the subject is non existent with the instruction. - James, Udemy Student
Lessons were clear and engaging - Bridgette, Udemy Student
great tricks for remembering hard concepts - Babu, Udemy Student
This Master Geometry Course includes over 50 lectures that will introduce students to many topics including triangles and their angles, geometric proofs, and mathematical logic. The students' progress will be measured along the way through practice videos and quizzes that contain examples following almost every new topic. This course can be broken into a few key categories: