Question

A line passes through the points (-1,0), (1, 2), and (-8, y). What is the value of y?

a) -2
b) -6
c) -10
d) -12

Answer 1

To find the value of y, use the slope-intercept form of a linear equation and substitute the given points. The value of y is -7.

Step-by-step explanation:

To find the value of y, we can use the slope-intercept form of a linear equation, which is y = mx + b, where m is the slope and b is the y-intercept.

Step 1: Calculate the slope (m) using the formula: m = (y2 - y1) / (x2 - x1). Using the points (-1,0) and (1,2), we can substitute the values into the formula: m = (2 - 0) / (1 - (-1)) = 2/2 = 1.

Step 2: Choose one of the points (-1,0) or (1,2) and substitute the values into the slope-intercept form of the linear equation to find the y-intercept (b). Using the point (-1,0), we can substitute the values into the formula: 0 = 1*(-1) + b. Solving for b, we get b = 1.

Step 3: Substitute the values of m and b into the slope-intercept form of the linear equation: y = 1*x + 1. Finally, substitute the x-coordinate of the third point (-8) to find the value of y. y = 1*(-8) + 1 = -8 + 1 = -7.

Therefore, the value of y is -7.