
David W. answered 05/31/15
Tutor
4.7
(90)
Experienced Prof
First, I’d recommend learning to translate words into precise, concise math notation:
For a right triangle with sides A, B, and C:
“The hypotenuse of a right triangle is 5ft long” means C = 5ft
“The shorter leg is 1ft shorter than the longer leg” means A + 1 = B
Now, the math:
A2 + B2 = C2 [ Pythagorean Theorem]
A2 + (A+1)2 = 25
A2 + A2 + 2A + 1 = 25
2A2 + 2A – 24 = 0
So,
A = (-2 + SQRT(4+192))/4 or A = (-2 – SQRT(4+192))/4
A = 3 or A = -4 (but A must be positive)
And
A + 1 = B
4 = B
Checking:
Is 32 + 42 = 52 ? yes.
p.s., this triangle -- 3x, 4x, 5x – will appear in lots of problems and on lots of tests!
Peter J.
05/31/15