Answer:
A=7
Step-by-step explanation:
You wanna add the -3a into the other -a but you'd be adding that -3a. You would end up getting 14=2a,then you would divide that 2 into itself and the 14 giving you a=7
7
collect like terms
14=-a+3a
2a=14
dividing both sides
a=7
12
i need an picture then I will help you out
Answer:B 28 cm^2
