Digital SAT Math Test 6 Question 8

For the linear function $g$, the table shows three values of $x$ and their corresponding values of $g(x)$. Function $g$ is defined by $g(x)=ax+b$, where $a$ and $b$ are constants. What is the value of $a-b$?
Answer:
B

Explanation

The correct answer is Choice B.

Substitute any two pairs of coordinates into the given function in order to find $a$ and $b$, and therefore, $a-b$.

Choices A, C, and D are incorrect and may result from algebraic mistakes.

✨ Expert's Tip ✨

You can also find $a$, which is the slope of the linear function, using the slope formula: $m=\frac{y_2-y_1}{x_2-x_1}$.

    About Exxcel

    Exxcel was established by a team of dedicated educators and experienced test writers who share a common goal: to equip students with the tools they need to excel in their exams. As an online Digital SAT® test preparation platform, our mission is to empower students to realize their full potential through mentorship and the delivery of high-quality, accessible education.

    College Board® is a trademark registered by the College Board, which is not affiliated with, and does not endorse, this website. Exxcel is unaffiliated with College Board® and do not have access to College Board's proprietary data.