SAT Math Multiple Choice Question 789: Answer and Explanation
9. If the slope of the equation shown above is 6, what is the value of c?
- A. –4
- B. -
- D. 4
Correct Answer: B
Category: Heart of Algebra / Linear Equations
Strategic Advice: Don't overthink a question like this. It is asking about slope and you have an equation, so write the equation in slope-intercept form and see where that takes you.
Getting to the Answer: When an equation is written in slope-intercept form (y = mx + b), m is the slope of the line. Rewrite the given equation in this form by subtracting from both sides and then dividing both sides by c:
Now, set the coefficient of x equal to the given slope (6) and solve for c. The coefficient is a fraction, so write 6 as and cross-multiply:
The value of c is - , which is (B).