91Ó°ÊÓ

Subtract. $$ -7-14 $$

Perform the indicated operation and, if possible, simplify. If there are no variables, check using a calculator. $$ \frac{13}{18}-\frac{4}{9} $$

Subtract. $$ -8-0 $$

Subtract. $$ -9-0 $$

Subtract. $$ 2-25 $$

Evaluate. $$ -x^{2}-5 x, \text { for } x=-3 $$

Subtract. $$ 18-63 $$

In each of Exercises \(71-78,\) match the phrase or sentence with the appropriate expression or equation from the column on the right. One less than the product of two numbers is 49_____ a) \(\frac{x}{y}+6\) b) \(2(x+y)=48\) c) \(\frac{1}{2} \cdot a \cdot b\) d) \(t+2=5\) e) \(a b-1=49\) f) \(2(m+n)\) g) \(3(t+5)\) h) \(x-5=9\)

Write each expression in two equivalent forms, as in Example \(6 .\) $$ \frac{9}{-a} $$

Subtract. $$ -5.8-(-7.3) $$