Question

Question 5(Multiple Choice Worth 1 points)

Answer 1

Given:

The graph passes through the points (0,-20) and (4,10).

To find:

The equation of line that most closely represents the line depicted in the graph.

Solution:

If a line passing through two points, then the equation of line is

$y-y_1=\dfrac{y_2-y_1}{x_2-x_1}(x-x_1)$

The given line passes through the points (0,-20) and (4,10). So, the equation of line is

$y-(-20)=\dfrac{10-(-20)}{4-0}(x-0)$

$y+20=\dfrac{10+20}{4}(x)$

$y+20=\dfrac{30}{4}x$

$y+20=\dfrac{15}{2}x$

Subtracting 20 from both sides, we get

$y=\dfrac{15}{2}x-20$

The function form is

$f(x)=\dfrac{15}{2}x-20$

f of x equals fifteen halves times x minus 20.

Therefore, the correct option is B.