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3 years ago

WILL GIVE FIRST ANSWER BRAINLIEST

Mathematics

2 answers:

koban [17]3 years ago

6 0

Answer: The correct option is (D) (5, -2).

Step-by-step explanation: We are given to use the method of substitution to solve the following system of equations :

$3x+7y=1~~~~~~~~~~~~~~~~~~~~~~~~~(i)\\\\y=x-7~~~~~~~~~~~~~~~~~~~~~~~~~~~~(ii)$

Substituting the value of y from equation (ii) in equation (i), we get

$3x+7y=1\\\\\Rightarrow 3x+7(x-7)=1\\\\\Rightarrow 3x+7x-49=1\\\\\Rightarrow 10x=50\\\\\Rightarrow x=\dfrac{50}{10}\\\\\Rightarrow x=5,$

and from equation (ii) again, we get

$y=x-7=5-7=-2.$

Thus, the required solution is (x, y) = (5, -2).

Option (D) is CORRECT.

DedPeter [7]3 years ago

4 0

My answer is D.(5, -2)

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