Question

Which of the following equations represent a line that passes through the points below

(-2,-8) (0,2)

A: y= -5x+5
B: y=5x+5
C:y=1/5x+5
D: y=-1/5+5

Answer 1

Hey there again!

First, let's find the slope of this line. We will divide the difference in the y's by the difference in the x's.

`(y)/(x) =(2+8)/(0+2) =(10)/(2) = 5`

Our slope is 5, so our equation should look like this so far.

y=5x+b

But, the only answer that matches having a slope of 5 is B, so we don't even need to finish!

Therefore, our answer is B: y=5x+5

I hope this helps! Have a great day!

Answer 2

The equation of a straight line can be represented in the slope-intercept form, y = mx + c

Where c = y intercept

m represents the slope of the line.

m = (y2 - y1)/(x2 - x1)

y2 = final value of y

y 1 = initial value of y

x2 = final value of x

x1 = initial value of x

The line passes through (- 2, - 8) and (0, 2),

y2 = 2

y1 = - 8

x2 = 0

x1 = - 2

Slope,m = ( 2 - - 8)/(0 - - 2) = 10/2 = 5

To determine the y intercept, we would substitute x = 0, y = 2 and m = 5 into y = mx + c. It becomes

2 = 5 × 0 + c

2 = 0 + c

c = 2

c = - 8

The equation becomes

y = 5x + 2