4x + 3 = -5x + 21
9x + 3 = 21
9x = 18
x = 2
Hope this helps!! :)
c and e are expressions.
b is an equation.
a and d are inequalities.
Expressions are the only ones WITHOUT an 'equals', 'greater', or 'less than'.
( = , > ,. < )
What item do you want the most? Once you tell me this I can write your whole essay.