SAT Math Formulas
Linear Equations or Linear Models—ANSWER--1. 𝑦=𝑚𝑥+𝑏.
ALWAYS use this equation...ALWAYS for lines.
2. Parallel lines have the SAME slope
3. Perpendicular lines' slopes are NEGATIVE RECIPROCALS
Two points (x,y) in a graph/table/word problem?—ANSWER--1. Two points =
the slope somehow unlocks it
2. If you see one point or no labeled points, find them and use them in this
formula
Percents over 100—ANSWER--1. Take 100%
2. Add the new percent (e.g. 14%)
,3. Get 114%
4. Make decimal 1.14 (move decimal TWO to the LEFT)
5. Pops up in Exponential Mode questions as the rate
Function Notation—ANSWER--They will give you 𝑓(𝑥) = equation
To find f(4); 4 is in the parentheses = 4 is the x value; plug 4 in for x
If 𝑓(𝑥) = 4, then set the equation = to 4 and olve for x
Direct variation—ANSWER--1. Usually will give you equation of 𝑦 = 𝑘𝑥 and
two scenarios
2. Plug in corresponding values for first scenario, solve usually for K
3. Plug in k and other value to solve the second scenario
© 2026 Copyright. All Rights Reserved. This document is
protected by copyright law, Copyrighted By Brittie Donald
, Absolute Value Expressions/Equations—ANSWER--1. Always as two
answers (unless it is equal to 0)
2. Solve the equation as is without the absolute value
signs. That is one solution
3. Also negate ALL WITHIN the absolute value sign and
solve. That is the other solution
4. Many of these problems are DESMOS-friendly
Linear vs. Exponential Growth—ANSWER--1. Linear growth = constantly
added or subtracted value
a. Usually has the word "constant" in the problem
2. Exponential growth = constantly multiplied or divided value
Linear Equations or Linear Models—ANSWER--1. 𝑦=𝑚𝑥+𝑏.
ALWAYS use this equation...ALWAYS for lines.
2. Parallel lines have the SAME slope
3. Perpendicular lines' slopes are NEGATIVE RECIPROCALS
Two points (x,y) in a graph/table/word problem?—ANSWER--1. Two points =
the slope somehow unlocks it
2. If you see one point or no labeled points, find them and use them in this
formula
Percents over 100—ANSWER--1. Take 100%
2. Add the new percent (e.g. 14%)
,3. Get 114%
4. Make decimal 1.14 (move decimal TWO to the LEFT)
5. Pops up in Exponential Mode questions as the rate
Function Notation—ANSWER--They will give you 𝑓(𝑥) = equation
To find f(4); 4 is in the parentheses = 4 is the x value; plug 4 in for x
If 𝑓(𝑥) = 4, then set the equation = to 4 and olve for x
Direct variation—ANSWER--1. Usually will give you equation of 𝑦 = 𝑘𝑥 and
two scenarios
2. Plug in corresponding values for first scenario, solve usually for K
3. Plug in k and other value to solve the second scenario
© 2026 Copyright. All Rights Reserved. This document is
protected by copyright law, Copyrighted By Brittie Donald
, Absolute Value Expressions/Equations—ANSWER--1. Always as two
answers (unless it is equal to 0)
2. Solve the equation as is without the absolute value
signs. That is one solution
3. Also negate ALL WITHIN the absolute value sign and
solve. That is the other solution
4. Many of these problems are DESMOS-friendly
Linear vs. Exponential Growth—ANSWER--1. Linear growth = constantly
added or subtracted value
a. Usually has the word "constant" in the problem
2. Exponential growth = constantly multiplied or divided value
