Respuesta :
The Pythagorean theorem states that for a rigth triangle, the square of the hypothenuse is equal to the sum of squares of the other two sides, symbolically:
[tex]a^2+b^2=c^2[/tex]To check if these sides lengths are of a rigth triangle you have to square them.
Remember that the hypothenuse is always the longest side.
So for the first set:
A)
3cm, 4cm and 5 cm
Lets take the side length 5cm as the hypothenuse
So a=3, b=4 and c=5
If the theorem checks then
[tex]3^2+4^2=5^2[/tex]Square all sides:
[tex]\begin{gathered} 3^2=9 \\ 4^2=16 \\ 5^2=25 \end{gathered}[/tex]Add both squared sides:
[tex]9+16=25[/tex]The result is equal to the square of the hypotenuse, this means that this side lengths corresponds to a rigth triangle.
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B)
a=3 cm
b=5 cm
c=9 cm (hypothenuse)
Square the three sides:
[tex]\begin{gathered} a^2=3^2=9 \\ b^2=5^2=25 \\ c^2=9^2=81 \end{gathered}[/tex]If the theorem checks then 9 + 25 must be equal to 81
[tex]9+25=34[/tex]The square sum of both sides is different from the quare of the hypotenuse, these side lengths do not correspond to a rigth triangle.
C)
a=12cm
b= 16 cm
c= 20 cm (hypothenuse)
Square the sides:
[tex]\begin{gathered} a^2=12^2=144 \\ b^2=16^2=256 \\ c^2=20^2=400 \end{gathered}[/tex]If the theorem checks then 144 plus 256 must be 400
[tex]144+256=400[/tex]The sum of squares of the sides is equal to the square of the hypothenuse, this set of side lengths belong to a right triangle.
D)
a=16cm
b=63cm
c=65cm (hypothenuse)
Square the sides:
[tex]\begin{gathered} a^2=16^2=256 \\ b^2=63^2=3969 \\ c^2=65^2=4225 \end{gathered}[/tex]If the theorem checks out, then 256 + 3969 must be equal to 4225:
[tex]256+3969=4225[/tex]The sum of squares of the sides is equal to the square of the hypothenuse, this set of side lengths belong to a right triangle.
