These two angles are equivalent because they're corresponding angles created by two parallel lines.
Since they're equivalent, we can set them equal to each other.
23x - 5 = 21x + 5
Now solve for x
23x - 5 = 21x + 5
Add 5 to both sides
23x = 21x + 10
Subtract 21x from both sides
2x = 10
Divide both sides by 2
x = 5
Now, plug in 5 as "x" in one of the equations
Angle 1 = (23*5) - 5
= 115 - 5
= 110 degrees
Since they're equivalent, Angle 2 should also be 110 degrees, but let's check in case.
Angle 2 = (21*5) + 5
= 105 + 5
= 110 degrees
