Question

What is the value of a in the following equation? -23=-2a-10+a

Answer 1

simplify both sides 
-23=-2a+10+a
-23=(-2a+2a)+(10) <-- combine like terms
-23=-a+-10
-23= -a -10
Flip the equation
-a -10=-23
add 10 to both sides
-a -10(+10) =-23(+10)
-a=-13
divide both sides by -1
-a/-1=-13/-1
answer a=13 
Hope this helped :))