Question

The work of a student to solve a set of equations is shown:

Equation A: y = 15 – 2z
Equation B: 3y = 3 – 4z


Step 1:
–3(y) = –3(15 – 2z) [Equation A is multiplied by –3.]
3y = 3 – 4z [Equation B]


Step 2:
–3y = 15 – 2z [Equation A in Step 1 is simplified.]
3y = 3 – 4z [Equation B]


Step 3:
0 = 18 – 6z [Equations in Step 2 are added.]


Step 4:
6z = 18


Step 5:
z = 3



In which step did the student first make an error? (5 points)


Step 4


Step 3


Step 2


Step 1

Answer 1

The answer is C. Step 2

Hope This Helps!

Answer 2

The student made error in step 2 because negative multiplied by positive is negative. Also negative multiplied by negative is positive