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What is the value of x? How can you check your answer?

What is the value of x? How can you check your answer?-example-1
User Sumit S Chawla
by
2.5k points

1 Answer

7 votes
7 votes

Answer:

x = 75

Explanation:

Hi there!

Let's start by looking at the two parallel lines, l and m, and the diagonal line that crosses both of them. Line l and this diagonal line create the angle that measures (2x-30)°.

For a second, let's pretend that the 45°, x° and the straight line aren't there. The diagonal line and line m would create the alternate exterior angle of the angle that measures (2x-30)°. (Please see the attached image.)

Alternate exterior angles are equal in measure.

Now, with this knowledge, we now know that (2x-30)° is equal to 45+x:

2x-30 = 45+x

x-30 = 45

x = 75

Therefore, the value of x is 75.

To check your answer, you can substitute x into (2x-30)° and find the angle. It equals 120°. 45+75 is equal to 120°, so therefore, this answer is correct.

I hope this helps!

What is the value of x? How can you check your answer?-example-1
User Xiomy
by
3.1k points