Question

If shown, line AB and line CD are straight lines. Find x in each case.

Answer 1

x = 45

Explanation:

To find x, derive an equation from the figure given.

Angles on a straightline = 180°. Therefore:

Combine like terms

Subtract 135 from both sides

x=45

Answer 2

x = 45

Explanation:

To find x, derive an equation from the figure given.

Angles on a straightline = 180°. Therefore:

`15 + x + 2x + 120 - 2x = 180`

Combine like terms

`15 + 120 + x + 2x - 2x = 180`

`135 + x = 180`

Subtract 135 from both sides

`135 + x - 135 = 180 - 135`

`x = 45`