Question

The line through (5,k) and (3,8) has a slope of 4, How might I find what k is?

Answer 1

\[m=\frac{y2-y1}{x2-x1}\]

just substitute

Answer 2

Lets do the formula y=mx+b

we know that the slope is 4 so we can replace m with 4.

y=4x+b

We can plug in the coordinate that we know (3,8) into the equation

8=4(3)+b

8=12+b
-12-12
-4=b

y=4x-4

k=4(5)-4
k=20-4
k=16

(5,16)

Lets graph and check!

Answer 3

Actually we can use @marco26's response and check

8-16/3-5
-8/-2
4

Answer 4

cool, thanks!