7. 3.14(12^2 - 10^2)=3.14(144-100) = 3.14(44)=138.16
8. A = piR^2 = 50.24. R^2 = 50.24/3.14 = 16. R = 4cm
9a) Perimeter of square is 4*18 = 72. Perimeter of circle is 2*pi*r. r=9in
perimeter of circle is then 2*3.14.9 = 56.52. Difference is 72-56.52 = 15.48
9b) Area of square is 18^2 = 324.
Area of circle is 3.14(9^2) = 254.34. Difference is the unshaded part
324-254.34 = 69.66in^2
Step-by-step explanation: The letter "x" is often used in algebra to mean a value that is not yet known. It is called a "variable" or sometimes an "unknown". In x + 2 = 7, x is a variable, but we can work out its value if we try!
Answer:
A. 66
Step-by-step explanation:
Team A scored:
78+66=144
78-66=12 so Team A scored 12 fewer points than Team B
