Question

Write in equation of the line containing the points (-8,-8) and (-9,-10

Answer 1

y = 2x + 8

Explanation:

Find the slope of a line between (-8,-8) and (-9,-10) using m =
`(y_2-y_1)/(x_2-x_1)`, which is the change in y over the change in x.

Substitute in the values of x and y into the equation to find slope.

`m= (-10-(-8))/(-9(-8))`

Simplify.

Simplify the numerator.

Multiply -1 by -8

`m=(-10+8)/(-9-(-8))`

Add -10 and 8

`m=(-2)/(-9-(-8))`

Simplify the denominator.

Multiply -1 by -8

`m=(-2)/(-9+8)`

Add -9 and 8.

`m=(-2)/(-1)`

Divide -2 by -1.

`m=2`

Using the point slope form
`y-y_1=m(x-x_1)` plug in m = 2,
`x_1 = -8, y_1 = -8`

`y-(-8)=(2)(x-(-8))`

Solve for y.

Multiply -1 by -8

y + 8 = ( 2 ) ( x − ( − 8 ) )

Simplify ( 2 ) ( x − ( − 8 ) ) .

Multiply − 1 by − 8

y+8 = 2 ( x + 8 )

Apply the distributive property.

y + 8 = 2 x + 2 ⋅ 8

Multiply 2 by 8 .

y + 8 = 2x + 16

Move all terms not containing y to the right side of the equation.

Subtract 8 from both sides of the equation.

y = 2 x + 16 − 8

Subtract 8 from 16 .

y = 2 x + 8