Can someone please Solve x^2+2x -3 =x^2

Noor brought 21 sheets of stickers. she gave 1/3 of a sheet to each of the 45 students at recess. she wants to give teachers 1 1/2 sheets each.

Rewrite the following quadratic functions in intercept or factored form. show your work. f(x) = 3x^2 - 12

Use the quadratic function to predict f(x) if x equals 8. f(x) = 25x2 − 28x + 585