Vertical angles x and 65

Step by step

The question

Question: find x when two lines cross and the opposite angles are x and 65°.

1 Use the angle fact

Where two lines cross, the opposite angles are equal.

They are called vertical angles.

So x is the same as 65°: x = 65.

2 Check

The angle x is 65°, the same as the opposite angle.

So x = 65 is right!

Let's look back.

First: use the angle fact.

Last: check.