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Triangle ABC has perimeter 22cm

AB=8cm
BC=5cm
by calculation deduce whether triangle ABC is a right-angled triangle

User Avi Cherry
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1 Answer

9 votes

Answer:

the triangle is not right-angled

Explanation:

First of all, we are told that the perimeter of the triangle is 22 and the two sides are given, 8cm and 5cm respectively. This means that the third side is: 22-(8+5) = 9cm

From this as see that 9cm is the highest length we have and if it were a right-angled triangle, this could be the hypotenuse. Now, to be sure of the initial response we use the Pythagoras theorem. We know that the hypotenuse² = adjacent² + opposite²

let's use the measurements we are given in the question

8²+5²=AC²

64+25=89

AC=√89

AC=9.433981132

AC =9.43cm

and when we add 8+5+9.43 to calculate the perimeter we get 22.43 which is not the initial perimeter, this the triangle isn't right-angled

User Ove Stoerholt
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