Identify the intersection by equating the lines' y-values. Demonstrate with y = x + 2 and y = 2x + 1 to solve x = 1 and y = 3.

Calculate the circumference of a circle using c = 2πr with r = 7 cm; applying π = 22/7 yields a circumference of 44 cm.

Compute arc length using the central angle and radius with the formula length = (theta/360) × 2πr, shown for a 7 cm circle and 18° angle, giving about 2.2 cm.

Calculate the length of the chord in a circle using B = 2 r sin(theta/2). With r = 10 cm and theta = 60°, the chord length is 10 cm.

Compute the area of a sector from a 40-degree angle, using the radius squared, and conclude the sector area is eight thousand square centimeters.

The example shows finding the area of a circle segment by subtracting triangle area from the sector, using a 10 cm radius and 16 cm chord, yielding 52 square centimeters.

Explore right angled triangles, apply c^2 = a^2 + b^2 to relate hypotenuse and legs, and practice calculating the hypotenuse from two given sides, as in a 4–3–5 example.

Master parallelogram properties, including opposite sides being equal and opposite angles equal when lines intersect, within basic geometry concepts for SAT and ACT math.

Explore trapezoids, a four-sided shape with one pair of parallel sides, including regular and irregular types, where the parallel sides may differ in length and the other sides vary.

Explain that a square has four equal sides and two diagonals intersecting at right angles, then use Pythagoras to find the diagonal and compute area from the side.

Explore quadrilaterals, four-sided shapes such as square, rectangle, rhombus, and trapezoid, and distinguish convex from concave by diagonals; interior angles always sum to 360 degrees.

Discover how to find the number of diagonals in a polygon using the n choose 2 minus n formula, with pentagon and octagon examples.

Explore hemisphere formulae for surface area and volume, including surface area as 3 pi r^2, and volume as half of a sphere.