In short the answer is the width = 6 and the length = 12.
Explanation:
You can solve this by creating equations. Let L stand for length and W for width. The original rectangle can be represented by the equation
2L + 2W = 36
The second rectangle can be represented by the equation
2(L+13) + 2(2W) = 74
simplifying we get
2L + 26 + 4W = 74
subtracting 26 from each side we get
2L + 4W = 48
This is a system of equations, which can be solved by subtracting the second equation from the first, which will cancel out the 'L' variable. If we do this, we get
-2W = -12
so W = 6
Plugging back into the first equation to solve for L:
2L + 2(6) = 36
2L + 12 = 36
2L = 24
L = 12