I need help on this question. Can someone explain?

Answer : A triangle equals 180 degrees.

If you add all of the sides , they should equal 180.

2x + 1X-3 + 7 = 180

After you add the X’s together, and the numbers together (NOT including the 180 after the equal sign) you’ll get the equation.

So , the equation is written like this :

3x+4 = 180

So , from there , you can solve from x.

After you solve for x , replace the x for the actual numbers.

Example :

2x
Instead of the x , insert the number.

And insert the number for x-3

7 doesn’t have an x , so leave it alone