M equals 3x+21 because you add 2x+1x=3x.then you add 14+7=21.then you combine them together to get 3x+21
The correct answer would be C
Where/what slopes are I talking about?
Point slope form:

m=slope
(x1,y1)
First we need to find the slope using the slope formula:

Given the two coordinates:
<span>(1, 9) and (−1, 11)
Plug them into the slope formula:
</span>

Simplify:

<span>
Now we know that:
m=-1 and the (x1,y1) would be </span><span>(1, 9)
</span>
Now we simply plug in the info:
Final answer: y − 9 = −(x − 1)
Answer:
mixed number form: 9 1/3
decimal form: 9.3 (repeating)
Step-by-step explanation: