Question

Write an equation of the line shown. Then use the equation to find the value of x when y=112

Answer 1

Answer:

$y = 8x + 16$

$x = 12$

Step-by-step explanation:

Given two points on the line (0, 16) and (3, 40), an equation for the line can be written using the slope-intercept line equation which takes the format $y = mx + b$.

Where,

$m = slope = \frac{y_2 - y_1}{x_2 - x_1}$

b = y-intercept or the point at which the line cuts the y-axis.

Let's find slope (m) using the slope formula:

Let,

$(0, 16) = (x_1, y_1)$

$(3, 40) = (x_2, y_2)$

$slope (m) = \frac{40 - 16}{3 - 0}$

$slope (m) = \frac{24}{3}$

$slope (m) = 8$

Find b. Substitute the values of x = 0, y = 16, and m = 8 in the slope-intercept formula to find b.

$y = mx + b$

$16 = 8(0) + b$

$16 = 0 + b$

$16 = b$

$b = 16$

Plug in the values of m and b into the slope-intercept formula to get the equation of the line.

$y = mx + b$

$y = 8x + 16$

Let's use the equation to find x when y = 112.

$y = 8x + 16$

Substitute y = 112 in the equation

$112 = 8x + 16$

$112 - 16 = 8x$

$96 = 8x$

Divide both sides by 8

$12 = x$

$x = 12$