Umm.. just multiply the pi out in the first one so
pi(x^2+12x+36) = pi*(x^2) + pi*(12x) + pi*(36) and you are subtracting pi*x^2 so you get pi*(12x) + pi*(36). Then you can factor the pi*12 and get (pi*12)(x+3)
Umm.. just multiply the pi out in the first one so
pi(x^2+12x+36) = pi*(x^2) + pi*(12x) + pi*(36) and you are subtracting pi*x^2 so you get pi*(12x) + pi*(36). Then you can factor the pi*12 and get (pi*12)(x+3)