Irene R. answered 03/20/20
Math Teacher :13+ years; Tutor for 3rd to 12th grade for 18+ years
Let' s use the variable x to represent the length of the longer leg.
Then we can represent the length of the hypotenuse with the following expression: x + 7
Also the length of the shorter leg can be represented by: x - 7
Using the Pythagorean Theorem , a2 + b2 = c2, we can write:
(x - 7) 2 + x2 = (x + 7)2
Solving this equation:
x2 - 14x + 49 + x2 = x2 + 14x + 49
2•x2 - 14 x + 49 = x2 + 14 x + 49
2•x2 - 14 x + 49 - x2= x2 + 14 x + 49 - x2
x2 -14 x + 49 = 14 x + 49
x2 -14 x + 49 - 49 = 14 x + 49 - 49
x2 -14 x = 14 x
x2 -14 x + 14 x = 14 x + 14 x
x2 = 28 x
x2 /x = 28x/x
x = 28
The longer leg would be 28 cm
The hypotenuse would be x + 7 = 28 + 7 = 35 cm
The shorter leg would be x -7 = 28 - 7 = 21 cm