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3 years ago

Use the elimination method to solve the system of equations. Choose the

Mathematics

2 answers:

MatroZZZ [7]3 years ago

6 0

Answer:

Step-by-step explanation:

7x + 3y = 30 (equation 1)

-2x + 3y = 3 (equation 2)

9x = 27 (subtract the two equations to eliminate y)

x = 3 (divide by 9)

7 * 3 + 3y = 30 (Substitute x = 3 into equation 1, it doesn't matter which equation you substitute into)

21 + 3y = 30 (7 * 3 = 21)

3y = 9 (Subtract 21)

y = 3 (divide by 3)

Answer is (3, 3)

Nikitich [7]3 years ago

3 0

Answer:

(3,3)

Step-by-step explanation:

7x + 3y = 30

-2x + 3y= 3

Multiply the second equation by -1 and add together to eliminate y

7x + 3y = 30

2x - 3y= -3

---------------------

9x + 0y = 27

Divide by 9

9x/9 = 27/9

x = 3

Now find y

-2x+3y = 3

-2(3) +3y =3

-6 +3y = 3

Add 6 to each side

3y = 3+6

3y=9

Divide by 3

y = 3

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Using the problem statement as the basis for the equation, we can write ...

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Using the diagram as the basis for the equation, we could write it as ...

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