Practice - Algebra 1

2.4.5 Practice

2.4.5 • Practice

Complete the following questions to practice the skills you have learned in this lesson.

For questions 1 – 8, solve the systems of equations using the elimination method.

$\begin{array}{c}\left\{\begin{array}{l}5x\;+\;2y\;=\;2\\-6x\;-\;2y\;=\;0\end{array}\right.\\\\\end{array}$

$(–2,6)$
$(2,–4)$
$(0,1)$
$(–3,9)$

$\begin{array}{c}\left\{\begin{array}{l}2x\;-\;5y\;=\;7\\-15x\;+\;5y\;=\;-85\end{array}\right.\\\\\end{array}$

$(−4,−3)$
$(6,1)$
$(5,−2)$
$(7,4)$

$\begin{array}{c}\left\{\begin{array}{l}6x\;-\;10y\;=\;-18\\25x\;+\;10y\;=\;80\end{array}\right.\\\\\end{array}$

$(4,−2)$
$(0,8)$
$(7,6)$
$(2,3)$

$\begin{array}{c}\left\{\begin{array}{l}-6x\;-\;16y\;=\;6\\6x\;+\;15y\;=\;-9\end{array}\right.\\\\\end{array}$

$(7,–2)$
$(1,–1)$
$(–9,3)$
$(–14,5)$

$\begin{array}{c}\left\{\begin{array}{l}-15x\;-\;40y\;=\;-335\\15x\;+\;9y\;=\;180\end{array}\right.\\\\\end{array}$

$(6,10)$
$(17,2)$
$(9,5)$
$(12,0)$

$\begin{array}{c}\left\{\begin{array}{l}x\;-\;3y\;=\;-9\\x\;+\;\frac52y\;=\;2\end{array}\right.\\\\\end{array}$

$(–9,0)$
$(2,0)$
$(0,3)$
$(–3,2)$

$\begin{array}{c}\left\{\begin{array}{l}x\;+\;\frac13y\;=\;3\\2x\;+\;\frac13y\;=\;5\end{array}\right.\\\\\end{array}$

$(2,3)$
$(0,15)$
$(0,9)$
$(3,0)$

$\begin{array}{c}\left\{\begin{array}{l}3x\;-\;8y\;=\;-35\\-5x\;+\;8y\;=\;45\end{array}\right.\\\\\end{array}$

$(–1,4)$
$(–5,2.5)$
$(7,7)$
$(–9,0)$

For questions 9 – 10, add the equations in the following systems of equations. What is the resulting new equation?

$\begin{array}{c}\left\{\begin{array}{l}4x\;-\;6y\;=\;14\\-4x\;+\;y\;=\;-19\end{array}\right.\\\\\end{array}$

$\begin{array}{c}\left\{\begin{array}{l}3x\;-\;5y\;=\;18\\7x\;+\;5y\;=\;-8\end{array}\right.\\\\\end{array}$