Question the-li

1.1 Linear Functions - Slope calculation and interpretation
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  • The line slants sharply up from left to right.
  • The line passes through the following points:
    • (0 comma 5)
    • (1 comma 9)

Line j is shown in the xy-plane. Line k (not shown) is parallel to line j . What is the slope of line k ?

Enter your answer:

The line slants sharply up from left to right. The line passes through the following points:

Medium-difficulty · SAT Math · Linear Functions — Slope calculation and interpretation. Read the question above, select your answer, and check the full explanation below to understand exactly why the correct choice works.

Answer explanation

The correct answer is 4 . It's given that line k is parallel to line j . It follows that the slope of line k is equal to the slope of line j . Given two points on a line in the xy-plane, x1,y1 and x2,y2, the slope of the line can be calculated as y2-y1x2-x1. In the xy-plane shown, the points 0,5 and 1,9 are on line j . It follows that the slope of line j is 9-51-0, or 4 . Since the slope of line j is equal to the slope of line k , the slope of line k is also 4 .