The sides are 12, 16, and 20
For a Right Triangle we can use the Pythagorean Theorem
Let x = Short Leg
x + 4 = Longer Leg
x + 8 = Hypotenuse
x2 + (x + 4)2 = (x + 8)2
x2 + x2 + 8x + 16 = x2 + 16x + 64
Combine like terms
2x2 + 8x + 16 = x2 + 16x + 64
Subtract x2, 16x and 16 from both sides of the equation to give
2x2 - x2 + 8x - 16x = 64 - 16
x2 - 8x = 48
We can set up a quadratic to find x
x2 - 8x - 48 = 0
(x - 12)(x + 4)
x cannot be negative so x = 12
x = 12 = Shortest Side
x + 4 = 16 = Longer Side
x + 8 = 20 = Hypotenuse
Checking
122 + 162 = 202
144 + 256 = 400
400 = 400
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