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ERROR ANALYSIS Describe the error in solving for one of the variables in the linear system 4x + 3y = 8 and x-2y=-13x4x+3y6x-2y=-13 Multiply by4x + y = 5-4x+By=-1311y=-5y"71o The right side of the second equation was not multiplied by -4..The left side of the second equation was multiplied by 4o The expression 3y – By equals -5y, not lly.O The expression 8 - (- 13) equals 21.not -5.Correct the error by solving for y.

ERROR ANALYSIS Describe the error in solving for one of the variables in the linear-example-1
User Daahrien
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1 Answer

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We can see from the picture of the question that the error in solving this system of linear equations was that when the second equation was multiplied by -4. We need to multiply the whole equation, including the right side of the equation. We can see that:


-4\cdot((x-2y)=-13)=-4\cdot x+(-4)\cdot(-2y)=-4\cdot(-13)

And the result must be:


-4x+8y=52

And the second equation was: -4x + 8y = -13 (this is not correct.)

Therefore, the right side of the equation was not multiplied by -4 (this was the error.) (First option.)

The correct answer is:

Substituting this value in the first equation, we can, then, find the value for x:


4x+3((60)/(11))=8\Rightarrow4x+(180)/(11)=8\Rightarrow4x=8-(180)/(11)

ERROR ANALYSIS Describe the error in solving for one of the variables in the linear-example-1
ERROR ANALYSIS Describe the error in solving for one of the variables in the linear-example-2
User Lexx
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