Question

I need help with this problem! I Don't know how to solve this problem! Please help me.

Answer 1

You would do:
2x^2 = 16^2
X^2 = 128
X = 8 root2

Answer 2

So.. notice the ratios there,
those ratios are good, when the triangle is
made up of, two 45 degree angles, 
and one 90
thus is called a 45-45-90 angle

the two legs are the same length
and the hypotenuse, or longest leg, 
whatever the others are, times square root
of 2

so.. one could say that $\bf 16=x\sqrt{2}\implies \cfrac{16}{\sqrt{2}}=x \\ \quad \\ \textit{now, we could rationalize that by} \\ \quad \\ \cfrac{16}{\sqrt{2}}\cdot \cfrac{\sqrt{2}}{\sqrt{2}}=x\implies \cfrac{16\sqrt{2}}{(\sqrt{2})^2}=x\implies \cfrac{16\sqrt{2}}{2}=x\implies 8\sqrt{2}=x$