91Ó°ÊÓ

For exercises 1-4, rewrite the repeating decimal as a fraction. $$ 0 . \overline{38} $$

For exercises 1-4, rewrite the repeating decimal as a fraction. $$ 0 . \overline{51} $$

Mixture A is \(31 \%\) acid. Find the amount of this mixture and the amount of water needed to make \(410 \mathrm{~L}\) of a new mixture that is \(24 \%\) acid. Round to the nearest whole number.

For exercises 3-4, (a) identify the substitution expression. (b) find the \(x\)-coordinate of the intersection point. (c) find the \(y\)-coordinate of the intersection point. (d) identify the solution of the system. (e) check. $$ \begin{aligned} &6 x+y=13 \\ &y=3 x+4 \end{aligned} $$

For exercises 5-40, (a) solve by substitution. (b) if there is one solution, check. $$ \begin{aligned} &y=3 x-5 \\ &3 x+2 y=17 \end{aligned} $$

For exercises 5-36, (a) solve by elimination. (b) if there is one solution, check. $$ \begin{array}{r} 3 x+y=1 \\ -3 x+y=7 \end{array} $$

Mixture A is \(13 \%\) merlot grape juice. Find the amount of pure merlot grape juice to add to this mixture to make 59 gal of a new mixture that is \(44 \%\) merlot grape juice. Round to the nearest whole number.

Graph. Label the solution region.a $$ \begin{aligned} &3 x+2 y>18 \\ &y<4 x+5 \end{aligned} $$

(a) solve by elimination. (b) if there is one solution, check. $$ \begin{aligned} 2 x+y &=-2 \\ -2 x+y &=10 \end{aligned} $$

(a) solve by substitution. (b) if there is one solution, check. $$ \begin{aligned} &y=2 x-5 \\ &2 x+5 y=23 \end{aligned} $$