RenB
PQR is an isosceles right-angled triangle with perimeter 8 + 8√2 and longest side PR. What is the length of side PR?
A. 4
B. 8
C. \(4\sqrt{2}\)
D. \(8\sqrt{2}\)
E. 16
Perimeter = 8 + 8√2
We know triangle is an isosceles triangle
...that means two sides are equal
...so the two equal sides are either 4+4=8 or 4√2+4√2=8√2
...
we know that the sum of longer side must be less than the sum of two sides and greater than the difference of two sides...that means hypotenuse is <8 or <8√2
...if we assume two sides are 4 and 4
then 8√2 = 8 × 1.4 = 11.2 which is greater than sum of two sides (8) so the two sides are not equal to 4 each.
...if we assume two sides are equal to 8√2 = 11.4 then the longer side can be 8 because it is less than the sum of two sides.
Therefore,
option B is the answer. Time to solve: 30 seconds
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