Question

A line that passes through the point (x,y), with a y-intercept of b and a slope of m, can be represented by the equation y = mx + b.

A line is drawn on the coordinate plane that passes through the point (3,-6) and has a slope of 4. The y-intercept of the line is .

Answer 1

b= -18

Explanation:

x=3, y= -6, m=4

y=mx+b

-6 = 4 x 3 + b Solve for b

-6 = 12 + b

-6-12 = b

b= -18

Answer 2

b = -18

Explanation:

Slope y-intercept form: y =mx +b

Slope = m = 4

Plugin the value of slope in the above equation.

y = 4x + b

Now, the line passes through the point (3 , -6). Substitute x and y coordinates in the above equation.

-6 = 4*3 + b

-6 = 12 + b

b = -6 - 12

b = -18

`\sf \boxed{\bf y-intercept = -18}`