# Need help solving an equation

#### christinel

##### New member
Hi, it's been a while since I have done algebra, and I cannot for the life of me remember how to solve this type of equation....
I am actually trying to find the measure of an angle....a ray is coming off of a straight line, one of the angles measures x + 10 and I'm trying to find the measure of the angles...any hoo, this is the equation I have come up with, but my x's keep zeroing out:

(x+10) + (180-(x+10)) = 180

#### Subhotosh Khan

##### Super Moderator
Staff member
christinel said:
Hi, it's been a while since I have done algebra, and I cannot for the life of me remember how to solve this type of equation....
I am actually trying to find the measure of an angle....a ray is coming off of a straight line, one of the angles measures x + 10 and I'm trying to find the measure of the angles...any hoo, this is the equation I have come up with, but my x's keep zeroing out:

(x+10) + (180-(x+10)) = 180

Your calculations are correct.

When "x's keep zeroing out" - it means that any value of "x" will satisfy that equation (which has turned into an - what we call - identity).

We cannot find a "unique" value of x from that relation.

#### mmm4444bot

##### Super Moderator
Staff member

You have not provided enough information to determine any specific value for x.

Mathematically, x can be any Real number.

EG:

Let's say that x is 20 degrees.

x + 10 is 30 degrees

180 - 30 is 150 degrees

The 30-degree angle and the 150-degree angle are called "supplementary angles" because their sum is 180 degrees.

Let's say that x is 137 degrees.

x + 10 is 147 degrees

180 - 147 is 33 degrees

The 147-degree angle and the 33-degree angle are supplementary.

Are you able to provide a more-detailed description of what you're trying to accomplish ?

When you say that a ray is coming off a straight line, the angle between them can be anything larger than zero degrees and smaller than 180 degrees.

We need more information about how x is related to the scenario.

Cheers ~ Mark 