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Estimate the solution to the system of equations. -3x+3y=9 2x-7y=-14

A. x=-2 2/5 , y=1 3/5
B. x=-1 2/5 , y=2 3/5
C. x=-1 2/5 , y=1 3/5
D. x=-2 2/5 , y=2 3/5

User Coxx
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1 Answer

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The estimated solution to the system of equations is x = -7/2 and y = -1/2. Represented as a mixed number, x = -3 1/2. The closest match among the options is C. x = -1 2/5, y = 1 3/5.

To estimate the solution to the system of equations -3x + 3y = 9 and 2x - 7y = -14, we can use the elimination method:

Multiply the first equation by 2 to make the coefficients of x in both equations equal:

-6x + 6y = 18

Now, the system becomes:

-6x + 6y = 18

2x - 7y = -14

Adding these equations eliminates x:

-x - y = 4

Now, solving for y:

y = -x - 4

Substitute this expression for y into one of the original equations, let's use the first one:

-3x + 3(-x - 4) = 9

Simplify:

-3x - 3x - 12 = 9

Combine like terms:

-6x - 12 = 9

Add 12 to both sides:

-6x = 21

Divide by -6:

x = -7/2

Now substitute this value of x back into the expression for y:

y = -(-7/2) - 4 = 7/2 - 4 = -1/2

So, the estimated solution is x = -7/2 and y = -1/2.

To represent the solution as a mixed number, x = -7/2 can be expressed as x = -3 1/2.

Therefore, the closest match from the given options is:

C. x = -1 2/5, y = 1 3/5.

User Shubham Azad
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