Which equation has both 4 and -4 as possible values of y?

Oscar and julie ashton are celebrating their 15th anniversary by having a reception hall. they have budgeted $4,500 for their reception. if the reception hall charges a $90 cleanup fee plus & 36 per person, find the greatest number of people that they may invite and still stay within their budget.

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

What is the value of m in the equation 1/2 m - 3/4n=16 when n=8