The answer is “B. y = 3x + 4”
Explanation:
To find the slope of two points, we need to use the formula m=rise/run or m=y2-y1/x2-x1
-2-7 -9
m = ——— = — = 3
-2-1 -3
Now we have to find “b” as in the equation “y=mx+b”
We already have our “m” which is the slope and that is equal to 3
In order to fine “b,” we have to set it up in point slope form which is the formula
“y-y1 = m(x-x1)”
You can choose to set this up with either one of the coordinates given
In this problem, the coordinates given are
(-2, -2) and (1, 7)
I’m going to use the coordinates (1, 7)
y-y1 = m(x-x1)
y-7 = 3(x-1)
The “7” is the y point
The “3” is the slope
The “1” is the x point
Now we simplify the equation:
y-7 = 3(x-1)
y-7 = 3x-3
+7 +7
—————
y = 3x + 4
Hope this helps and makes sense :)
