Answer: 35.5
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Step-by-step explanation:
The triangles are identical. So this means that the triangle on the left has the horizontal portion of 50 ft, and the other sides are x ft (where x is a placeholder for a number).
Add up the sides for the either triangle. We have x+x+50 = 2x+50. This expression is the perimeter of one triangle. The perimeter of both triangles is simply us doubling that expression
combined perimeter of 2 triangles = 2*(perimeter of one triangle)
combined perimeter of 2 triangles = 2*(2x+50)
combined perimeter of 2 triangles = 2*(2x)+2*(50) ... distribute
combined perimeter of 2 triangles = 4x+100
We're told that the combined perimeters total 242 ft, so this means 4x+100 must equal 242
Solve for x
4x+100 = 242
4x+100-100 = 242-100 ... subtract 100 from both sides
4x = 142
4x/4 = 142/4 ... divide both sides by 4
x = 35.5
note: 35.5 feet = 35 feet, 6 inches because 1/2 ft = 0.5 ft = (0.5*12) inches = 6 inches