SAT Math Multiple Choice Practice Question 168: Answer and Explanation
Asked to estimate an equation for the data pictured above, a student drew a line connecting points A and B. The equation that would most closely fit this line would be
A. y = -3x + 100
B. y = 3x + 100
D. y = -3x + 95
Correct Answer: A
A. Point A is at (2, 95); point B is at (14, 60). The slope of the line connecting them is , which is very close to -3. Because this line slopes downward, it would rise about 6 units as you moved left from 2 to 0, which means the y-intercept would be around 95 + 6 = 101. Thus, (A) is your best choice.