1.
We will write and solve an equation that expresses the given relation. Let x represent the angle measure. Its complement is (90-x).
... x =(1/4)(90 -x)
Subtract x and simplify
... 0 = (90/4) - (5/4)x
Divide by the coefficient of x, which is -5/4.
... 0 = -18 +x
Add the opposite of the constant.
... 18 = x
The angle is 18°.
2.
The attachment shows the intersction of road AB with road CD.
Supplementary angles: ∠CXA and ∠CXB; ∠BXC and ∠BXD; ∠DXA and ∠DXB; ∠AXC and ∠AXD.
Complementary angles: none
Vertical angles: ∠AXC and ∠BXD; ∠BXC and ∠AXD.