Question 331978
Let A = the angle.  Its supplement is (180-A) and this is what you want to find.
From the problem description, we can write:
A = 2(180-A)+15 "An angle (A) measures 15 degrees more than twice its supplement." First, we need to find the value of angle A.
A = 2(180-A)+15  Multiply the quantity in the parentheses by 2 using the distrbutive property.
A = 360-2A+15 Simplify this.
A = 375-2A Add 2A to both sides.
3A = 375 Now divide both sides by 3.
A = 125 degrees, and its supplement is:
180-A = 180-125 = 55 degrees.