SOLUTION: The longer leg of a right triangle is 1cm longer than the shorter leg and the hypontenuse is 5cm, then what are the lengths of the leg?

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Question 148002: The longer leg of a right triangle is 1cm longer than the shorter leg and the hypontenuse is 5cm, then what are the lengths of the leg?
Found 2 solutions by Alan3354, Electrified_Levi:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
L = short side
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L%5E2+%2B+%28L%2B1%29%5E2+=+5%5E2
L%5E2+%2B+L%5E2+%2B+2L+%2B1+=+25
2L%5E2+%2B+2L+-+24+=+0
L%5E2+%2B+L+-+12+=+0
(L + 4)*(L - 3) = 12
L = 3
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2nd side = 4

Answer by Electrified_Levi(103) About Me  (Show Source):
You can put this solution on YOUR website!
Hi, Hope I can help
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The longer leg of a right triangle is 1 cm. longer than the shorter leg and the hypontenuse is 5cm, then what are the lengths of the leg?
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The shorter leg is represented by "x", the longer leg is (x+1)
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We will use the Pythagorean theorem to solve for the two sides, the Pythagorean theorem equation is
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+a%5E2+%2B+b%5E2+=+c%5E2+
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"a" and "b" are the sides, "c" is the hypontenuse. We will now replace "a", "b" , and "c"
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+%28x%2B1%29%5E2+%2B+x%5E2+=+5%5E2+
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+%28x%2B1%29%5E2+%2B+x%5E2+=+25+
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We will solve it even more
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+%28x%5E2+%2B+2x+%2B1%29+%2B+x%5E2+=+25+
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+x%5E2+%2B+2x+%2B1+%2B+x%5E2+=+25+
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+2%28x%29%5E2+%2B+2x+%2B1+=+25+
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We will move the "25" to the left side
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+2%28x%29%5E2+%2B+2x+%2B1+-25+=+25+-+25+
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+2%28x%29%5E2+%2B+2x+-+24+=+0+
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We can reduce the equation, we will divide everything by "2"
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+%282%28x%29%5E2+%2B+2x+-+24%29%2F2+=+0%2F2+
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+x%5E2+%2B+x+-+12+=+0+
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We can use the quadratic equation
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+x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
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This is the original equation using "a", "b", and "c"
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+a%28x%29%5E2+%2B+%28b%29x+%2B+c+=+0+
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+x%5E2+%2B+x+-+12+=+0+
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a = 1, b = 1, c = -12
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Now we can replace them in the quadratic equation,
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+x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
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+x+=+%28-1+%2B-+sqrt%28+1%5E2-4%2A1%2A%28-12%29+%29%29%2F%282%2A1%29+
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+x+=+%28-1+%2B-+sqrt%28+1-%28-48%29+%29%29%2F2+
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+x+=+%28-1+%2B-+sqrt%28+1+%2B+48%29%29%2F2+
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+x+=+%28-1+%2B-+sqrt+%2849%29+%29%2F2+
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+x+=+%28-1+%2B-+7+%29%2F2+
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We will use addition(if we used subtraction, the answer would be negative)
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+x+=+%28-1+%2B+7+%29%2F2+
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x+=+6%2F2+
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x+=+3+
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x = 3 cm.( lengths or measurements can't be negative, the other answer would be (-4) )( you can check by replacing "x" in +%28x%2B1%29%5E2+%2B+x%5E2+=+25+ with "3"
or "-4"
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The shorter side was x, or 3 cm., the longer side was (x+1), or 4 cm.
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You can check by replacing "a" and "b" in the Pythagorean theorem equation
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+a%5E2+%2B+b%5E2+=+c%5E2+
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+4%5E2+%2B+3%5E2+=+5%5E2+
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+16+%2B+9+=+25+
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+25+=+25+
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Shorter side = 3 cm.
Longer side = 4 cm.
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Hope I helped, Levi