Question

Line CD passes through points C(1, 3) and D(4, –3). If the equation of the line is written in slope-intercept form, y = mx + b, what is the value of b?

–5
–2
1
5

Answer 1

Answer: D. 5

Step-by-step explanation: First we need to find the slope

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

= (-3-3)/(4-1)

=-6/3

= -2

Then we can use point slope form to make the equation

y-y1 = m(x-x1)

y-3 = -2(x-1)

Distribute

y-3 = -2x+2

Add 3 to each side

y-3+3 = -2x+2+3

y = -2x+5

Since this is in slope intercept form, y = mx +b, the y intercept is 5

Answer 2

5

Explanation:

First we need to find the slope

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

= (-3-3)/(4-1)

=-6/3

= -2

Then we can use point slope form to make the equation

y-y1 = m(x-x1)

y-3 = -2(x-1)

Distribute

y-3 = -2x+2

Add 3 to each side

y-3+3 = -2x+2+3

y = -2x+5

Since this is in slope intercept form, y = mx +b, the y intercept is 5