SOLUTION: In parallelogram DATE, angle D = 8x-20 and angle A = 2x+30. Find x. I was thinking that both angles had to be equal, so i set the equation equal and i came out with a decimal po

Algebra ->  Parallelograms -> SOLUTION: In parallelogram DATE, angle D = 8x-20 and angle A = 2x+30. Find x. I was thinking that both angles had to be equal, so i set the equation equal and i came out with a decimal po      Log On


   



Question 408151: In parallelogram DATE, angle D = 8x-20 and angle A = 2x+30. Find x.
I was thinking that both angles had to be equal, so i set the equation equal and i came out with a decimal point. Thank you for your help.

Answer by katealdridge(100) About Me  (Show Source):
You can put this solution on YOUR website!
They're not equal, they are supplementary. So you have to add them and set it equal to 180.
8x-20+2x+30=180 combine like terms
10x+10=180 subtract 10 from both sides
10x=170 divide both sides by 10
x=17