Key geometric concepts, proofs, and theorems
What is the sum of interior angles in a triangle?
The sum of interior angles in any triangle is always 180 degrees
In similar triangles, corresponding sides are:
Similar triangles have equal angles and proportional sides
What is the Pythagorean Theorem?
In a right triangle, the square of the hypotenuse equals sum of squares of legs
Find the area of a circle with radius 5
Area of circle = πr² = π(5)² = 25π
Two lines are perpendicular if their slopes:
If line1 has slope m, perpendicular line has slope -1/m