This is a 45-45-90 triangle and the ratios of the sides are 1 : 1 : sqrt2 where sqrt2 is the length of the hypotenuse ( longest side)
So the measure of x = 12 sqrt2 which is the first choice.
Answer:
Hi how are you doing today Jasmine
The length is 4 yards longer than 3width so L = 3W+4
perimeter equal 408 yards
perimeter equal 2L +2W = 2(3W+4)+2W
408 = 6W +8 +2W
400=8W
W = 50
L = 3*50 +4 = 154
L = 154
W = 50
P = 2L +2W
408 = 2*50 +2*154
408 = 100 +308
408 = 408
hope that this is easy understandably