SAT Formula Memorization

Discriminant Rules

D > 0 : 2 Real Solutions

D = 0 : 1 Real Solution

D < 0 : No Real Solutions

Area of Equilateral Triangle + Explanation for use in pyramid problems

gj

Double Side lengths of a square…

4x the area

Double side lengths of a cube

8x the area

Write Formula: You Put $100 into a savings account. It grows by 4% each year.

f(t) = 1000(1.04)^t

sin(x) =
cos(x) =

cos(90-x)

sin(90-x)

Sum of the solutions

x1 + x2 = -B / A

Product of the solutions

C / A

y-intercept of a polynomial

What makes a triangle similar?

Triangles are similar if their corresponding angles are equal and the lengths of their sides are proportional. just NOT SSA

Circle Equation

Increasing by 20%
Decreasing by 20%

Increasing by 150%

1.2

0.8x

2.5x

What is 150% more than 10?

2.5 × 10 = 25

Sum of (interior) angles

180(n-2)

Tangent line is ______ to the line that connects the center point and tangent point

perpendicular

Slope of a line in Standard Form (Ax + By = C)

m = -A / B

How to find the arc length

a = r * theta (theta/angle MUST be in radians)

6.1 something

Common Triangle Sides

3-4-5 triangles and 5-12-13 triangles

Triangle Inequality Theorem

Sum of lengths of two sides > length of third side

Completing the Square
Practice Problem:

answer should be radius = 5

If you have 4 constants/variables that are being solved for with DESMOS regression, do x1 = [1, 2..] for how many points?

4 points or more

How to get the X value of the vertex (and also the y value)

X-value: -B / 2A , Y-Value: Plug x back into original equation

Percent Change Formula

Example Q: 140 is p% greater than 10. What is p?

scale factor

If you triple the side lengths of a cube…

f ³ for 3D (volume)
f ² for 2D (area)
f for 1D (Linear)

…You 27x the volume. 3³ = 27.

Triangle Rules

Distance Formula (BUT USED IN DESMOS)

distance((2, 9), (2, 14))

30-60-90 triangle

45-45-90

random mad difficult question

284/3

vertex form

If <A + <B = 90…

Then cos(a) = sin(b)
and that means cos(a)-sin(b) = 0

distance of roots formula