Substitution
x-y=1
3x=3y+3

Jenisey has $24 to spend on seven pencils. after buying them she had $10. how much did each pencil cost.?

Angela is buying a dress that is on sale for 20% off. if the original price of the dress is $40.00, how much money is angela saving on the dress? a. $0.80 b. $3.20 c. $32.00 d. $8.00

Atown has a population of 12000 and grows at 3.5% every year. what will be the population after 7 years, to the nearest whole number?