Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

A variable needs to be eliminated to solve the system of equations below. Choose the correct first step.

{:[-6x+y=-8],[-6x+8y=-22]:}
Add to eliminate 
x.
Subtract to eliminate 
y.
Add to eliminate 
y.
Subtract to eliminate 
x.

A variable needs to be eliminated to solve the system of equations below. Choose the correct first step.\newline6x+y=86x+8y=22 \begin{array}{c} -6 x+y=-8 \\ -6 x+8 y=-22 \end{array} \newlineAdd to eliminate x \mathbf{x} .\newlineSubtract to eliminate y \mathbf{y} .\newlineAdd to eliminate y \mathbf{y} .\newlineSubtract to eliminate x \mathbf{x} .

Full solution

Q. A variable needs to be eliminated to solve the system of equations below. Choose the correct first step.\newline6x+y=86x+8y=22 \begin{array}{c} -6 x+y=-8 \\ -6 x+8 y=-22 \end{array} \newlineAdd to eliminate x \mathbf{x} .\newlineSubtract to eliminate y \mathbf{y} .\newlineAdd to eliminate y \mathbf{y} .\newlineSubtract to eliminate x \mathbf{x} .
  1. Analyze Variables for Elimination: Analyze the system of equations to determine which variable can be eliminated with the least amount of work.\newlineThe system of equations is:\newline6x+y=8-6x + y = -8\newline6x+8y=22-6x + 8y = -22\newlineWe can see that the coefficient of xx in both equations is the same (6-6), but the coefficients of yy are different (11 and 88). To eliminate xx, we would need to multiply the first equation by a number to make the coefficient of xx in the first equation the opposite of the coefficient of xx in the second equation. However, since the coefficients of xx are already the same (and opposite in sign), we can simply add the two equations together to eliminate xx.
  2. Perform Addition to Eliminate x: Perform the addition of the two equations to check if x is eliminated.\newlineAdding the two equations:\newline(6x+y)+(6x+8y)=8+(22)(-6x + y) + (-6x + 8y) = -8 + (-22)\newline6x+y6x+8y=30-6x + y - 6x + 8y = -30\newlineCombine like terms:\newline12x+9y=30-12x + 9y = -30\newlineWe can see that adding the equations does not eliminate x. This is because we have made a mistake in our calculation. We should have added the y terms, not the x terms, since we are trying to eliminate x.