Answer:The product of a number t and eight is twelve: t * 8 = 12
Twice the sum of a number m and five is the difference of nine and n: 2(m + 5) = 9 - n
Twenty-one is the quotient of a number y and 4: y / 4 = 21
Thrice the difference of number b and one is the product of a number c and ten: 3(b - 1) = c * 10
Explanation: