Plsss help'
Algebra
plzzz

Answer:
f(X)= 3x^2- 30x+5
Step-by-step explanation:
f(X)= 3(x-5)^2-70
= 3(x^2-2.x.5+ 5^2) -70
= 3(x^2-10x+25)-70
= 3x^2-30x+75-70
= 3x^2-30x+5