John is twice as old as mary. the sum of their ages is 21. how old is mary?
let j = john's age and m = mary's age.

In what form is the following linear equation written y=9x+2

Can someone check if i did this right since i really want to make sure it’s correct. if you do you so much

Ricky takes out a $31,800 student loan to pay his expenses while he is in college. after graduation, he will begin making payments of $190.66 per month for the next 30 years to pay off the loan. how much more will ricky end up paying for the loan than the original value of $31,800? ricky will end up paying $ more than he borrowed to pay off the loan.