use the ratio of a 45-45-99 triangle to solve for the variables.

Answers:
[tex]a = 18\sqrt{2}[/tex]
[tex]b = 18[/tex]
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Explanation:
For any 45-45-90 triangle, the two legs are the same length. We consider triangles like this to be isosceles. So we have b = 18 as the vertical leg because the horizontal leg is also 18 units long.
The hypotenuse of these types of triangles is always [tex]\sqrt{2}[/tex] times longer compared to the leg length. So the hypotenuse is [tex]a = 18\sqrt{2}[/tex]
As an alternative, you can use the pythagorean theorem to find the hypotenuse.