Hyung-eun is solving the quadratic equation x2−4x−12=0 by grouping. Her work is shown below. At which step does Hyung-eun first make an error? x2−4x−12=0 Step1: x2+(−6x)+2x−12=0 Step 2: (x2+(−6x))+(2x−12)=0 Step 3: x(x+(−6))+2(x−6)=0 x(x−6)+2(x−6)=0 Step 4: (x+6)(x−2)=0 Step 5: x+6=0 or x−2=0 x=−6 or x=2 (1 point) Responses Step 2 Step 2 Step 1 Step 1 Step 4 Step 4 Step 3

1 answer

Hyung-eun first makes an error in Step 3: x(x−6)+2(x−6)=0. The correct step should be x(x−6)+2(x−6)=0.