Question

Plz help me :(

Prove for any value of y the value of expression y^4−(y^2−9)(y^2+9) is divisible by 9.

Answer 1

Its 9*9

Explanation:

The equation equals 81 and 9*9=81.

Have a great day! :)

Answer 2

PROOF:

`y^4-(y^2-9)(y^2+9)\\=y^4 -(y^4-81)\\=y^4-y^4+81\\=81`

And 81 is ALWAYS divisible by 9