Area of a circle: πr²
Data:
diameter: 21 cm
radius=diameter/2=21 cm/2=10.5 cm
area of this circle: π(10.5 cm)²=110.25π cm² (≈346.36 cm²)
Answer: area=110.25π cm²
Divide 7 into 9 and if you have a calculator it equals 0.77 repeating
So if you distribute 4 in the first parentheses, you get 12x+20y+8z.
Then you distribute 3 in the second parentheses. You'll get 3x-3z. That all equals 12x+20y+8z+3x-3z.
Now you have to start combining numbers with the same variable. Start with x. 12x+3x is 15x.
y has no other common variable, it's left alone.
8z-3z is 5z
All together now with the numbers in simpler form, the equation is 15x+20y+5z
Jenna's would be the right answer because when you distribute 5 in her answer you get 15x+20y+5z
The answer is 0.444 repeating.