Answer:
(x+12)^2=84
Step-by-step explanation:
x^2+24x+60=0
x^2+24x=-60
x^2+24x+(24/2)^2=-60+(24/2)^2
(x+24/2)^2=84
(x+12)^2=84 (ans)
this may help you.look it once
Use disruptive property
