Mark is solving the following system.Step 1: He multiplies equation (1) by 7 and adds it to equation (3). Step 2: He multiplies equation (3) by 2 and adds it to equation (2). Which statement explains Mark’s mistake?
Answer
A
He added equation (3) instead of equation (2) in step 1.
B
He did not multiply equation (3) by the same number as equation (1).
C
He did not eliminate the same variables in steps 1 and 2.
D
He added equation the equations in step instead of subtracting them.