Answer:
3x
Explanation:
a = 4x - 4
The perimeter is equal to 14x + 8 but it is also equal to 2a + 2b, so
14x + 8 = 2(4x - 4) + 2b
14x + 8 = 8x - 8 + 2b
Let's move 2b to the other side of the equation, we get:
14x + 8 - 2b = 8x - 8
Now, let's move 14x + 8 to the other side too to find what -2b is equal to
-2b = 8x - 14x + 8 - 8
Gonna simplify:
-2b = -6x
Now, let's multiply both sides with -1 to find what 2b is equal to
-2b * -1 = -6x * -1
2b = 6x
Now, we know that 2*b is equal to 6x, but we need to find what side b is equal to, so we gonna divide 6x by two to get what b is equal to
2b = 6x
b = 3x
Side b is equal to 3x