Write a quadratic function f whose zeros are 4 and 1 .

Answer 1

f(x) = (x-4)(x-1)

= x^2 -5x + 1

or

y = x^2 -5x+ 1

take each zero, change its sign, stick an x in front of it, then multiply the factors together

4 becomes -4, then x-4

1 becomes -1, then x-1

multiply the factors together using FOIL (First product, Outside product Inside Product, Last product)

(x-4)(x-1) = x^2 -x -4x +1

combine the x terms to get

-4x-x = -5x

x^2 -5x +1