Can some one explain how to do it please. I am so confused.
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Hi there!
Your job, at least on this triangle, is pretty simple. This is a 45-45-90 triangle.
Because this is a 45-45-90 triangle, both legs are 5. That leaves us to find the hypotenuse, x.
And a 45-45-90 triangle's hypotenuse is easy. You just take the measure of one of the legs, or 5 in this case, and stick a [tex]\sqrt{2\\}[/tex] right next to it. So your answer will be:
[tex]5\sqrt{2}[/tex]
I hope this helps! :)