Question

Form the pair of linear equations for the following problems and find their solution by the substitution method.
The larger of two supplementary angles exceeds the smaller by $18$ degrees. Find them

Answer 1

Let x and y be two numbers.

$x-y=18$ …………..$\left(1\right)$

$x+y=180$ ………..$\left(2\right)$

From $\left(1\right)$, $y=x-18$

Substituting in $\left(2\right)$, we get

$x+x-18=180$

$2x=180+18$

$2x=198$

$x=99$

$y=x-18$

$=99-18$

$=81$

$\therefore$ The two angles are $99$ and $81$.