Answer:
D is the correct answer
Step-by-step explanation:
Answer:
I dont think it can be simplified
Step-by-step explanation:
Answer:
The answer is 27
Step-by-step explanation:
The reason being, you can solve this 2 ways.
1) Combine like terms, 7a-4a = 3a.
Now just substitute (a=9) into 3a.
3 * (9) = 27.
2) Or just substitute a = 9 into the original expression.
7 * (9) - 4 * (9)
= 63 - 36 = 27
1. D
2. B
3. A
4. C
Basically always use a^2 + b^2 = c^2 it gives you your A and C so subtract your A from you C and you have your B
