Hello from MrBillDoesMath!
Answer:
x = 4
Discussion:
Perimeter of rectangle:
= (x +13 + 2x) + (x +13 + 2x)
= 6x + 26
Perimeter of triangle:
(3x + 4) + (2x+5) + (5x + 1)
The diagram is a bit fuzzy but I think the above numbers are what is shown
= (3x + 2x + 5x) + (4 +5+1)
= 10x + 10
For the figures to have the same perimeter
6x + 26 = 10x + 10 => (subtract 6x from both sides)
6x - 6x + 26 = 10x - 6x + 10 =>
26 = 4x + 10 -> (subtract 10 from both sides)
26-10 = 4x =>
16 = 4x =>
x = 16/4 = 4
Check for triangle perimeter:
10x + 10 =
10(4) + 10 =50
Check for rectangle:
6x + 26
6(4) + 26 = 24 + 26 = 50
The number agree.
Thank you,
MrB
