SAT Math Calculator vs No-Calculator Reference Cheat Sheet

Key Facts

• On digital SAT Math, use quick estimation first so calculator results can be checked for reasonableness before selecting an answer.
• For a linear equation $ax + b = c$, solve by isolating the variable: $x = \frac{c - b}{a}$ when $a \ne 0$.
• For slope between two points, use $m = \frac{y_2 - y_1}{x_2 - x_1}$ and watch the order of subtraction.
• For a quadratic equation $ax^2 + bx + c = 0$, the quadratic formula is $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$.
• Exponent rules include $a^m a^n = a^{m+n}$, $\frac{a^m}{a^n} = a^{m-n}$, and $(a^m)^n = a^{mn}$ for $a \ne 0$.
• Percent change is $\frac{\text{new} - \text{original}}{\text{original}} \times 100\%$, and a percent increase by $r\%$ uses the multiplier $1 + \frac{r}{100}$.
• Circle formulas are $C = 2\pi r$ and $A = \pi r^2$, where $r$ is the radius.
• For right triangles, use $a^2 + b^2 = c^2$, and remember special ratios $45^{\circ}\text{-}45^{\circ}\text{-}90^{\circ}$ is $1:1:\sqrt{2}$ and $30^{\circ}\text{-}60^{\circ}\text{-}90^{\circ}$ is $1:\sqrt{3}:2$.

Vocabulary

Desmos

The built-in SAT graphing calculator that can graph equations, compare functions, solve systems visually, and check numerical answers.

Pacing

The strategy of managing time across questions so easier points are earned before spending extra time on harder problems.

No-calculator fluency

The ability to simplify, estimate, factor, and solve common equations accurately without relying on technology.

Slope

The rate of change of a line, calculated by $m = \frac{y_2 - y_1}{x_2 - x_1}$.

Discriminant

The expression $b^2 - 4ac$ in the quadratic formula that tells how many real solutions a quadratic equation has.

Multiplier

A decimal factor used for percent change, such as $1.15$ for a $15\%$ increase or $0.80$ for a $20\%$ decrease.