slope and intercept equation

Question

Write an equation of the line that passes through the given point
and has the given slope. Write your equation in slope-intercept form.

(4,-5);m=-3

Answer 1

Slope-intercept form line equation is y = mx + b. m is slope and b is y - intercept.

Step1. First find the y-intercept.

b (y - intercept) value can be found by replacing the x and y coordinate values in the equation with the given points. repalce m =-3 and (x, y) with (4, 5)

5 = -3 * 4 + b

5 = -12 + b

add 12 to each side

5 +12 =-12 +12 + b

 b = 17

Step2. Write the final line equation.

repalce m =-3 and b = 17 in Slope-intercept form line equation y = mx + b

y = -3x +17.

Comments

The point is (4, - 5).

- 5 = (- 3 * 4) + b

- 5 = -12 + b

b = - 5 + 12.

 b = 7.

The line equation is y = - 3x + 7.