Respuesta :

-243=-9(10+x)

-243=-90-9x
 +90  +90

-153=-9x _______________ divide -9 on both sides

x=17
miagwh
Answer: x = 17

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :
-243-(-9*(10+x))=0 
-243 - (0 - 9 • (x + 10)) = 0
9x - 153  =   9 • (x - 17) 

Equation at the end of step  3  : 9 • (x - 17) = 0 Step  4  

Solve: x-17 = 0
Add  17  to both sides of the equation : x = 17 

One solution was found :  x = 17