Question

Two straight parallel lines are cut by a transversal.

If the measures of two co-interior angles are $\left(2a{)}^{o}and\right(3a-10{)}^o$; find the value of 'a'.

Answer 1

Given the measures of two co-interior angles are ${\left(2a\right)}^o\&{(3a-10)}^o$.

We know that if the lines are parallel, the co-interior angles are supplementary.

So ${\left(2a\right)}^o+{(3a-10)}^o={180}^o\Rightarrow 5a=190\Rightarrow a=\frac{190}{5}\Rightarrow a={38}^o$