연립방정식 단원 종합

U.1Is the ordered pair a solution of the system? Write yes or no.

1. 1
   $(-5,3)$; $\{\begin{array}{l}4x-y=-23\\ 3x+y=-12\end{array}$ 
2. 2
   $(-1,-6)$; $\{\begin{array}{l}3x+y=-9\\ 5x-2y=-4\end{array}$ 

U.2Use the graph to solve each system.

1. 3
   $\{\begin{array}{l}y=-x+2\\ y=-4x+5\end{array}$ 
2. 4
   $\{\begin{array}{l}y=-2x+2\\ y=-x\end{array}$ 

U.3Solve each system by substitution.

1. 5
   $\{\begin{array}{l}y=4x+7\\ 5x-2y=-8\end{array}$
2. 6
   $\{\begin{array}{l}y=-4x+22\\ 3x-4y=45\end{array}$

U.4Solve each system by elimination.

1. 7
   $\{\begin{array}{l}x-9y=29\\ 3x-3y=-9\end{array}$
2. 8
   $\{\begin{array}{l}x+2y=10\\ 5x+6y=46\end{array}$

U.5Write one solution, no solution, or infinitely many solutions.

1. 9
   $\{\begin{array}{l}x-5y=25\\ 3x-15y=75\end{array}$
2. 10
   $\{\begin{array}{l}2x-5y=27\\ 4x+y=-1\end{array}$

U.6Write a system of equations and solve it.

1. 11
   $2$ notebooks and $4$ pens cost $\text{\$}20$. $1$ notebook and $1$ pen cost $\text{\$}6$. How much does each notebook and each pen cost?
2. 12
   A jar holds $16$ coins, all dimes and quarters, worth $\text{\$}2.20$ in all. How many of each coin are there?

U.7Solve each system, or write how many solutions it has.

1. 13
   $\{\begin{array}{l}2x+5y=33\\ x-5y=-36\end{array}$
2. 14
   $\{\begin{array}{l}x+15y=52\\ 5x-5y=20\end{array}$

U.1Is the Point a Solution of the System?

1. 1yes
2. 2no

U.2Solve Systems by Graphing

1. 3$(1,1)$
2. 4$(2,-2)$

U.3Solve Systems by Substitution

1. 5$(-2,-1)$
2. 6$(7,-6)$

U.4Solve Systems by Elimination

1. 7$(-7,-4)$
2. 8$(8,1)$

U.5Number of Solutions of a System

1. 9infinitely many solutions
2. 10one solution

U.6Systems of Equations Word Problems

1. 112 dollars per notebook, 4 dollars per pen
2. 1212 dimes, 4 quarters

U.7Systems of Equations Review

1. 13$(-1,7)$
2. 14$(7,3)$