#1**+1 **

If we conect WY.....we have an isosceles right triangle.... WY = 4sqrt (2) = √32

And angle WYX = 45.....so angle WYZ = 135 - 45 = 90

So...triangle WYZ is a right triangle with WZ the hypotenuse and WY a leg

So....by the Pythagorean Theorem

a = √ [ WZ^2 - WY^2 ] = √ [ 9^2 - (√32)^2 ] = √ [ 81 - 32 ] = √49 = 7

CPhill Nov 22, 2018