Question

Fan and Medal






Which of the following is not a perfect square trinomial?









A.

144 + 12y + y^2








B.

100 + 20y + y^2








C.

64 – 16y + y^2








D.

25 + 10y + y^2

Answer 1

1: 144 +24y +y^2 = y^2 +24y +144 = (y+12)(y+12)
2: 100 -20y +y^2 = y^2 -20y +100 = (y-10)(y-10)
3: 81 +18y +y^2 = y^2 +18y +81 = (y+9)(y+9)
4: 121 +11y +y^2 = y^2 +11y +121 = *** does not factor ****
5: m^2 +12m +36 = (m+6)(m+6)

Answer 2

D isn't a perfect square trinomial