## Elementary Technical Mathematics

a. We know that $\angle 2=\angle 3$ because they are alternate-interior angles, so $\angle 2=38^o$. Now $\angle 1+\angle 2=52^o+386^o=90^o$. That is $x\perp b$ and since $a\parallel b$, then $x\perp a$. b. As explained in (a), $x\perp b$.