how many solutions does this system have?
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Answer:
B. One
Step-by-step explanation:
Multiply the first equation by 2 and then add both equations to get rid of [tex]x[/tex]:
[tex]\begin{cases}2x+8y=18,\\-2x+y=0\end{cases}[/tex]
Adding both equations:
[tex]8x+y=18,\\9y=18,\\y=2[/tex]
Substituting [tex]y=2[/tex]:
[tex]-2x+2=0,\\-2x-2,\\x=1[/tex]
Therefore the only solution to the system of equations is (1, 2) and the system has one solution.