Answer:
\underline{\text{Variable Definitions:}}
Variable Definitions:
x=
x=
\,\,\text{the number of packs of cookies sold}
the number of packs of cookies sold
y=
y=
\,\,\text{the number of bags of chips sold}
the number of bags of chips sold
Each pack of cookies sells for $1, so xx packs of cookies will bring in 1x1x dollars. Each bag of chips sells for $2, so yy bags of chips will bring in 2y2y dollars. Therefore, the total amount 1x+2y1x+2y equals \$42:$42:
1x+2y=42
1x+2y=42
Since Kylie sold 3 times as many bags of chips as packs of cookies, she sold more bags of chips, so if we multiply 3 by the number of packs of cookies sold, we will get the number of bags of chips sold, meaning yy equals 3x.3x.
y=3x
y=3x
\underline{\text{Write System of Equations:}}
Write System of Equations:
1x+2y=
1x+2y=
\,\,42
42
y=
y=
\,\,3x
3x
\underline{\text{Solve for }y\text{ in each equation:}}
Solve for y in each equation:
\begin{aligned}\color{indianred}{1x}+2y = 42\hspace{10px} & \hspace{10px}\color{green}{y}\color{green}{=}\color{green}{3x} \\[10px] 2y = \color{indianred}{-1x}+42\hspace{10px} & \hspace{10px} & \\[10px] \frac{2y}{2} = \frac{-1x+42}{2}\hspace{10px} & \hspace{10px} & \\[10px] \color{blue}{y} \color{blue}{= -\frac{1}{2}x+21}\hspace{10px}\hspace{10px} & \hspace{10px} & \end{aligned}
1x+2y=42
2y=−1x+42
2
2y
=
2
−1x+42
y=−
2
1
x+21
y=3x
Explanation: