Question

If a line has a y-intercept of 12 and an x-intercept of 4, what would the value of y be when x = 20?

A) y = 0
B) y = 12
C) y = 24
D) y = 30

Answer 1

To find the value of y when x = 20 for a line with a y-intercept of 12 and an x-intercept of 4, calculate the slope as -3, and derive the equation y = -3x + 12. Substituting x = 20, y equals -48, which does not match any of the provided options.

Step-by-step explanation:

To find the value of y when x = 20 for a line with a y-intercept of 12 and an x-intercept of 4, we first need to determine the slope of the line (m).

The slope can be found using the formula m = (change in y) / (change in x).

In this case:

• The change in y is from 12 (at the y-intercept) to 0 (at the x-intercept).
• The change in x is from 0 (at the y-intercept) to 4 (at the x-intercept).

Thus, m = (0 - 12) / (4 - 0) = -3.

The equation of the line is then y = mx + b, where b is the y-intercept. Substituting the known values: y = -3x + 12.

To find y when x = 20:

y = -3(20) + 12

y = -60 + 12

y = -48

Therefore, the value of y when x = 20 is -48, which is not one of the provided options and suggests there may be an error in the options given.