Answer:
You need to memorize an
Elimination method
Multiply the first equation by -3,and multiply the second equation by 1:
−3(3x+y=−9)
1(9x+4y=−33)
Explanation:
Answer:
B. x=-1, y=-6
9x+4y=-33
3x+y=-9
9x+4y=-33
-4(3x+y=-9)
9x+4y=-33
-12x-4y=36
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-3x+0=3
x=-1
plug in the x to either original question
3(-1)+y=-9
y=-6
final answer: x=-1, y=-6