Answer: x = 9.611 ;or ; x = 9 11/18 . _________________________________________________ Explanation: ________________________________________________
All angles of any triangle must add up to 180 degrees.
So, (10x - 4) + (8x + 3) + 91 = 180 ; Solve for "x" ; ___________________________________________ 10x - 4 + 8x + 3 + 81 = 180 ;
Combine the "like terms" on the left-hand side of the equation: ___________________________________________ +10x + 8x = 18x ;
- 4 + 3 + 8 = 7 ; ____________________________ 18x + 7 = 180 ; ___________________________________________ Subtract "7" from each side of the equation: ___________________________________________ 18x + 7 - 7 = 180 - 7 ; ___________________________________________ to get:
18x = 173 ; _________________________________ Divide EACH side of the equation by "18" ; to isolate "x" on one side of the equation; and to solve for "x" ; _________________________________ 18x / 18 = 173 / 18 ; _________________________________ x = 9.6111111111111111.... _____________________________________
