Answer:
12
Step-by-step explanation:
Equation: 5x + 9 - 4x
Plug in x = 3
New equation: 5(3) + 9 - 4(3)
Simplify: 15 + 9 - 12
Simplify: 12
Answer: 12
x+9
5+9−4
1+9
x + 9