2 evens is an positive
1 odd,1 even is a odd
2 odd is an ofd
The square of a binomial expands as follows:

Expanding all the binomials, we have

Sum like terms:

Simplify terms appearing on both sides:

Move all terms involving k to the left and all numbers to the right:

Divide both sides by -20:

Answer:
a. 254.34, b. 56.52
Step-by-step explanation:
a. A = πr^2,
A = 3.14(9^2)
A = 3.14*81
A = 254.34
b. C = πd
C = 18*3.14
C = 56.52
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each video costs 40 points
total of 999 points
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