–0.28 − 10y = –8.3y + 6.01 how do u get y im so confused

Two times a number plus three times another number equals 4. three times the first number plus four times the other number is 7. find the numbers

Aprojectile is thrown upward so that its distance above the ground after t seconds is given by the function h(t) = -16t2 + 704t. after how many seconds does the projectile take to reach its maximum height?

When solving this problem: 3025/5.5 = a/90.75 you get 49912.5 which would be the length of one of the sides of a square when the area is only 90.75 inches. is that answer correct, why, and how is it possible?