Question 964088
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To be a right triangle, the sum of the squares of the legs must equal the square of the longest side (hypotenuse):
{{{a^2+b^2=c^2}}}
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a. 5in., 12in., 13in. 
{{{5^2+12^2=13^2}}} 
{{{25+144=169}}}
{{{169=169}}} True
ANSWER: Yes 
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b. 9in., 12in., 15in.
{{{9^2+12^2=15^2}}}
{{{81+144=225}}}
{{{225=225}}} True
ANSWER: Yes
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c. 3in., 3in., 4in.
{{{3^2+3^2=4^2}}}
{{{9+9=16}}}
{{{18=16}}} FALSE
ANSWER: No
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d. 6in., 10in., 12in.
{{{6^2+10^2=12^2}}}
{{{36+100=144}}}
{{{136=144}}} FALSE
ANSWER: No
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e. 8in., 8in., 8in.
This triangle is equilateral, so it can not be a right triangle.
ANSWER: No