Answer:

Step-by-step explanation:
Answer:
81
Step-by-step explanation:
2x+6=84
2x=78
81
find your own way
So you you are trying to find the area of sphere so you would use this formula
A=4•3.14•r^2
And you already know that the radius is 6 so you would go ahead and plug in the numbers
A=4•3.14•4^2
4^2 is 16 so your final equation would be
A=4•3.14•16
And your answer is
=452.39
Answer:
mm
kl l
Step-by-step explanation:
Answer:
The number is 2
Step-by-step explanation:
Twice a number (z) = 2*z = 2z
Twice a number (z) added to 21 = 2z + 21
9 times the number added to 7 = 9z + 7
9z + 7 = 2z + 21
Subtract 2z form both sides
9z - 2z + 7 = 21
7z + 7 = 21
Subtract 7 from both sides
7z = 21 - 7
7z = 14
Divide both sides by 7
z = 14/7
z = 2