Answer :
Here is what you know:
L = 3x
16 = 2L + 2x
Then substitute the L equation in for the 2L so you have:
16= 2(3x) + 2x
16= 6x + 2x
16= 8x
X = 2
L = 3x
16 = 2L + 2x
Then substitute the L equation in for the 2L so you have:
16= 2(3x) + 2x
16= 6x + 2x
16= 8x
X = 2