Kendra was given this system of equations. Negative 3 x + 7 y = negative 15. Negative 2 x minus 7 y = 5.

Kendra’s work is shown in the table. Where, if anywhere, did Kendra first make a mistake?

Steps
Kendra’s Work

Step 1

Negative 3 x + 7 y = negative 15. Negative 2 x minus 7 y = 5. Negative 5 x = negative 10.

Step 2

Negative 5 x = negative 10. x = 2.

Step 3

Negative 3 (2) + 7 y = negative 15. Negative 6 + 7 y = negative 15. 7 y = negative 9. y = Negative StartFraction 9 Over 7 EndFraction = negative 1 and StartFraction 2 Over 7 EndFraction