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3 years ago

14

Classify the system and determine the number of solutions. Check all that apply. {7x + y = 13 28x + 4y = -12 A) inconsistent B

)consistent C)infinitely many solution D) no solution

1 answer:

Ostrovityanka [42]3 years ago

4 0

$\left\{\begin{array}{ccc}7x+y=13&|multiply\ both\ sides\ by\ (-4)\\28x+4y=-12\end{array}\right\\+\left\{\begin{array}{ccc}-28x-4y=-52\\28x+4y=-12\end{array}\right\ \ \ |add\ the\ sides\ of\ the\ equations\\------------\\.\ \ \ \ \ \ \ \ 0=-64-FALSE\\\\Answer:A)\ inconsistent\ and\ D)\ no\ solution.$

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2 years ago

Read 2 more answers

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