Sagot :
QUESTION: The measure of the angles of a quadrilateral are x, x+15, x+25, and x+20 degrees. Find the measure of each angle of ABCD.
ANSWERS:
- m∠A = 75
- m∠B = 90
- m∠C = 100
- m∠D = 95
- Add the measures of all the angles.
- x + x + 15 + x + 25 + x + 20 = 4x + 60
- Make an equation. (360 is the sum of interior angles of quadrialateral)
- 4x + 60 = 360
- Solve using SPE and DPE (Subtraction Porperty of Equality and Division Property of Equality, respectively)
- 4x + 60 - 60 = 360 - 60
- 4x + 300
- [tex]\frac{4x}{4}[/tex] = [tex]\frac{300}{4}[/tex]
- x = 75
- The 60 gets cancelled out due to Inverse Property of Addition.
- Substitute the answer to x in the measures of all angles.
- m∠A = 75
- m∠B = 75 + 15 = 90
- m∠C = 75 + 25 = 100
- m∠D = 75 + 20 = 95
- Let me double check to make sure our answers are correct. To do this, add all our answers to see if their sum is 360.
- 75 + 90 + 100 + 95 = 360
- CORRECT!