Answer:
Step-by-step explanation:
hello :
ax+b =4x+9 so a=4 and b=9
You have known the formula Length of base is la division of Area and a haft of the height.
So we have 3

or


and

have fun
Answer: A is the answer
Explanation: A plane consist of 3 point but it can also be called by one specific point. And in the figure A there is one specific point. We can call it plane A