Can someone me ? marta tried solve the system below, but she made a mistake. read carefully and try to figure out what her mistake was. what was marta’s mistake? explain.

This mistake Marta made was that she substituted for y in the same equation where she made y the subject of the formula.

The system of equations that Martha is trying to solve is a simultaneous equation which she tried to solve using the substitution method.

10x + y = 22 equation 1

2x + y = -2 equation 2

Step 1: Make y the subject of the formula in equation 1

y = 22 - 10x

Step 2: Substitute for y in equation 2

2x + 22 - 10x = - 2

Step 3: Combine similar terms

2x - 10x = -2 - 22

-8x = -24

Step 4: divide both sides by -8

x = 3

This mistake Marta made is in step 2. Instead of substituting for y in equation 2 she substituted for y in equation 1.

To learn more about simultaneous equations, please check: link