As shown in the image:
There are two right triangles:
the triangle are similar
naming the points for easy calculation
measure of the angle zyw = measure of the angle yxw
And the measure of the angle ywz = measure of the angle xwy
So, the triangle WYZ will be similar to the triangle WXY
So, the corresponding side will be in proportion
![\begin{gathered} (wy)/(wx)=(wz)/(wy) \\ (a)/(16)=(4)/(a) \\ a^2=4\cdot16=64 \\ a=\sqrt[]{64}=8 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/d7byutagy5n2jlh86svcf4e82quy54lbov.png)
In the right triangle ywz:
using Pythagorean theorem:
![\begin{gathered} yz^2=yw^2+wz^2 \\ b^2=a^2+4^2=8^2+4^2=64+16=80 \\ b=\sqrt[]{80}=8.94 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/xvylmwhpdb2trgbfjlnsfw2sfxj34unt5x.png)