Question

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.

Answer 1

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:

$4x+3(\frac{60}{11})=8\Rightarrow4x+\frac{180}{11}=8\Rightarrow4x=8-\frac{180}{11}$