Answer:
4x - 7
Step-by-step explanation:
x + 2x + 3x - 2x = 4x
-8 + 1 = -7
Answer:
79 units²
Step-by-step explanation:
The area of a circle is found by using the formula A = π x r². Since we are not given the radius we can use the formula r = C / (2π). Substituting in the given values, we get r = 31.5/(2π). 2 times pi is 6.283185307. 31.5 divided by this will get you 5.013380707. Now, put that value in for r in the area equation. A = π x 5.013380707². Pi times 5.013380707² equals 78.96074613. This can be rounded to 79. (Or 80 if you need to the nearest whole number.)
There are a total of 208 cards. For every one card Tony has, Duane has 12, which means that there are 13 cards in each "set." If you divide the total number of cards (208) by 13, you get 16 "sets." So out of the total 208 cards, Tony has 16 cards and Duane has 12 times 16 or 192 cards.
