SOLUTION: can you help me with this:
2 legs of a right triangle have a total length of 21cm. hypotenuse is 15cm. Find the length of each leg of this right triangle.
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2 legs of a right triangle have a total length of 21cm. hypotenuse is 15cm. Find the length of each leg of this right triangle.
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Question 230704: can you help me with this:
2 legs of a right triangle have a total length of 21cm. hypotenuse is 15cm. Find the length of each leg of this right triangle. Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! X+Y=21 OR X=21-Y
X^2+Y^2=15^2
REPLACE THE X TERM IN THE SECOND EQUATION WITH (21-Y) & SOLVE FOR Y.
(21-Y)^2+Y^2=15^2
441-42Y+Y^2+Y^2=225
2Y^2-42Y+441-225=0
2Y^2-42Y+216=0
2(Y^2-21Y+108)=0
2(Y-12)(Y-9)=0
Y-12=0
Y=12 ANS. X=9 ANS.
Y-9=0
Y=9 ANS. X=12 ANS.
PROOF:
9^2+12^2=15^2
81+144=225
225=225
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