# geometry

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I need help on a question that wants me to find x and y on a 45-45-90 triangle they only give me one side wich is three.I already solved for x which is three root two over two...Is that right? I don't know how to solve for y... Please someone help me....:(

• geometry -

First we have to be clear where the x and the y are

You have an isosceles right-angled triangle (the 45-45-90)
If you let the hypotenuse be y, then each of the other sides is x
thus :
y^2 = x^2 + x^2
y^2 = 2x^2

if the given is x=3
then y^2 = 2(9) = 18
y = √18 = 3√2

if the given is y = 3
then 9 = 2x^2
3 = x√2
x = 3/√2 which rationalizes to 3√2/2
which is the answer you have.

So you will have to decide where the value of 3 is placed.

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