List A
4+4y=8y
4 (y-1)= 4
4y+1=5y
List B
4y-4=y
4 (y+1)=5y
1+4y=5y
Use substitution.
2p + 3(2p) = 680
2p + 6p = 680
8p = 680
p = 85
Plug in.
x = 2p
x = 2(85)
x = 170
p = 85
We can use point slope form to solve for this.
y - 1 = -2(x - 2)
Simplify.
y - 1 = -2x + 4
Add 1 to both sides.
y = -2x + 5
Now, we can input -3 for x and solve for y, or r in this case.
y = -2(-3) + 5
y = 6 + 5
y = 11
r = 11
(4)3 is also the same thing as 4x3 which is 12n
The answer is highlighted and I put the work for checking the answer at the bottom