EXERCISE

Statements $a$ and $b$ are as given below:

$a$: If two lines intersect, then the vertically opposite angles are equal. 

$b$:If a transversal intersects, two other lines, then the sum of two interior angles on the same side of the transversal is $180°$.

In the given figure, two lines $l$ and $m$ are intersected at $\mathrm{O}$. The value of $z$ is:

In the adjoining figure, it is given that $AO\parallel CD$, $OB\parallel CE$, and $\angle AOB=50°$. Find the measure of $\angle ECD$

Prove that lines which are parallel to the same line are parallel to each other

In the given figure, two straight line $AB$ and $CD$ intersect at a point $O$. If $\angle AOC = 42°$, find the measure of the angles $\angle AOD, \angle BOD \& \angle COB$.

Find the complement angle of 25$°$.

Find the complement angle of $72°$.

A road crosses a railway line at an angle of $30°$ as shown in Figure. Find the values of $a, b$ and $c$.