SOLUTION: If one side of a right triangle is 3 inches and the hypotenuse is 4 inches, how long is the other side? I need help with the formula and solution

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Question 208678: If one side of a right triangle is 3 inches and the hypotenuse is 4 inches, how long is the other side? I need help with the formula and solution
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
The 3 sides of every right triangle must fit the equation from the Pythagorean Theorem: a%5E2+%2B+b%5E2+=+c%5E2. The only "trick" is to understand that the hypotenuse, since it is always the longest side, must be the "c" in the equation. (It makes no difference which leg is "a" and which leg is "b".)

So we'll make the 3-inch leg "a" and the hypotenuse must be "c":
%283%29%5E2+%2B+b%5E2+=+%284%29%5E2
Now we just solve this to find "b", the other leg. Start by simplifying:
9+%2B+b%5E2+=+16
Subtract 9 from both sides:
b%5E2+=+7
Find the square root of both sides:
sqrt%28b%5E2%29+=+sqrt%287%29
abs%28b%29+=+sqrt%287%29
b+=+sqrt%287%29 or b+=+-sqrt%287%29
Since "b" represents the side of a triangle, we reject the negative solution. So the answer is that the third side of the triangle has a length of sqrt%287%29.