Which of the following best describes the expression 3x + 2y + 8z?

the product of three sums; there are three terms
the sum of three products; there are three terms
the product of three sums; there are six terms
the sum of three products; there are six terms

answer

Aswimming pool has an input pump for filling the pool and an output pump for emptying the pool. the input pump can fill the pool in 3 hours, and the output pump can drain the pool in 5 hours. as you go to bed, the pool is full, but a neighbor’s kid turns on the output pump. at midnight, you awake to find the pool half empty. immediately, you turn on the input pump, but you are sleepy and forget to turn off the output pump. at what time will the pool become full?

X+ y = 5 ; x - y =3 solve using linear combination

There are 45 questions on your math exam. you answered 810 of them correctly. how many questions did you answer correctly?