Question

Form the pair of linear equations for the following problems and find their solution by substitution method .

The larger of two supplementary angles exceeds the smaller by 18 degrees. Find them.

Answer 1

Let first angle = x

And second number = y

As both angles are supplementary so that sum will 180

x + y = 180

x = 180 - y ... (i)

Difference is 18 degree so that

x – y = 18

Putting the value of x we get

180 – y – y = 18

- 2y = -162

y = -162/-2

y = 81

Putting the value back in equation (i), we get

x = 180 – 81 = 99

Hence, the angles are 99º and 81º