Answer:
Every prism has as many faces, and edges, as its base has sides. Thus, a prism with an octagonal (eight sided) base has eight lateral faces, and eight lateral edges. Each lateral face meets two other lateral faces, as well as the two bases. As a consequence, each lateral face is a four sided polygon.
I think that you have forgot to divide at the end, like the first one would be 28 because you would divide by an estimate of 2
3x - 9y - 5x - 7y
Combine like terms
( 3x + - 5x ) + ( - 9y + - 7y )
= - 2x - 16y
With each of them saving $17 a week for 3 weeks, they will be able to save up $153 after three weeks. Adding this amount to the original amount they had will give them $467. Obviously, they will not have enough money to buy the gift they want for their mother. They will be short of $48.
