91Ó°ÊÓ

Simplify. $$ \frac{-6 x y z-3 x y+9 z}{-3} $$

Perform these computations. $$|-15|$$

Perform these computations. $$-|-75|$$

Solve each problem. Saving for college. The average cost of a B.A. at a private college in 2021 will be \(\$ 100,000\) (U.S. Department of Education, www.ed.gov). The principal that must be invested at interest rate \(r\) compounded annually to have \(A\) dollars in \(n\) years is given by the algebraic expression $$ \frac{A}{(1+r)^{n}} $$ What amount must Melanie's generous grandfather invest in 2005 at \(7 \%\) compounded annually so that Melanie will have \(\$ 100,000\) for her college education in \(2021 ?\)

Simplify. $$ \frac{20 a^{2} b^{4}-10 a^{2} b^{4}+5}{-5} $$

Perform these computations. $$\frac{1}{2}(-684)$$

Write an algebraic expression for each problem. Triangle. The lengths of the sides of a triangular flower bed are \(s\) feet, \(s+2\) feet, and \(s+4\) feet. What is its perimeter?

Write an algebraic expression for each problem. Parallelogram. The lengths of the sides of a lot in the shape of a parallelogram are \(w\) feet and \(w+50\) feet. What is its perimeter? Is it possible to find the area from this information?

Perform these computations. $$\frac{1}{3}(-123)$$

Solve each problem. Nursing home costs. The average cost of a 1 -year stay in a nursing home in 2007 was \(\$ 75,190\) (www.medicare.gov). In \(n\) years from 2007 the average cost will be \(75,190(1.05)^{n}\) dollars. Find the projected cost for a 1 -year stay in 2020