Question

use point-slope form to write equation of a line that passes through points (-1,4) and (-3,-5) in slope-intercept form

Answer 1

Answer:

y = 9x/2 + 17/2

Step-by-step explanation:

Use the slope formula: $(y_{2} - y_{1} )/ (x_{2} - x_{1})$ to find the slope of the line.

(4 - (-5)) / (-1 - (-3)) = (4 + 5) / (-1 + 3) = 9 / 2

y = mx + b

m is for slope, b = y-intercept

y = 9x/2 + b

Plug in one pair of the known values:

(-1,4)

4 = 9(-1)/2 + b

b = 4 + 9/2 = (8+9)/2 = 17/2

y = 9x/2 + 17/2

If you want to check if the equation is right, you can plug in the other pair of values into the equation:

(-3,-5), y = 9x/2 + 17/2

-5 = -3*9/2 + 17/2

-5 = -27/2 + 17/2

-5 = -10/2

-5 = -5