Subtract x from both sides
2x + 3 - x = -4
Simplify 2x + 3 - x to x + 3
x + 3 = -4
Subtract 3 from both sides
x = -4 - 3
Simplify -4 - 3 to -7
x = -7
2x+3=x-4
2x-x= -4-3
x= -7
Check answer by using substitution method
2(-7)+3= -7-4
-14+3=-11
-11=-11
Answer is x=-7
