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igomit [66]
3 years ago
9

Solve the system of equations below

Mathematics
1 answer:
DENIUS [597]3 years ago
4 0

Answer:

The answer is B. (-7,-2)

Step-by-step explanation:

Multiply the first equation by 7,and multiply the second equation by -6.

7(−3x+6y=9)

−6(5x+7y=−49)

Becomes:

−21x+42y=63

−30x−42y=294

Add these equations to eliminate y:

−51x=357

Then solve−51x=357for x:

−51x=357 Divide both sides by -51

x=-7

Write down an original equation:

−3x+6y=9

Substitute−7forxin−3x+6y=9:

(−3)(−7)+6y=9

6y+21=9(Simplify both sides of the equation)

6y+21+−21=9+−21(Add -21 to both sides)

6y=−12

y=-2

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Explanation:

Recall that quadratic form is ax^2+bx+c.

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