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3 years ago

Question 3(Multiple Choice Worth 4 points)

Mathematics

1 answer:

PilotLPTM [1.2K]3 years ago

4 0

Answer:

$\large\boxed{\left(-\dfrac{6}{5},\ -\dfrac{8}{5}\right)}$

Step-by-step explanation:

$\left\{\begin{array}{ccc}2x+y=-4&(1)\\y=3x+2&(2)\end{array}\right\qquad\text{substitute (2) to (1)}\\\\2x+(3x+2)=-4\\2x+3x+2=-4\qquad\text{subtract 2 from both sides}\\5x=-6\qquad\text{divide both sides by 5}\\\boxed{x=-\dfrac{6}{5}}\qquad\text{put it to (2)}\\\\y=3\left(-\dfrac{6}{5}\right)+2\\\\y=-\dfrac{18}{5}+\dfrac{10}{5}\\\\\boxed{y=-\dfrac{8}{5}}$

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