The polynomials f(x) = x^2 + bx + 400 have -20 as its only zero then the value of b is 40.
The polynomials f(x) = x^2 + bx + 400 have -20 as its only zero
Then x=-20
What is the zero of a polynomial?
The zeros of a polynomial p(x) are all the x-values that make the polynomial equal to zero.
x=-20 is the zero of the given polynomial
Therefore it satisfies the given polynomial
[tex]f(-20)=(-20)^2+b(-20)+400[/tex]
[tex]0=400-20b+400\\800-20b=0\\-20b=-800\\b=\frac{-800}{-20} \\b=40[/tex]
Therefore the value of b is 40.
To learn more about the zeros of the polynomials visit:
https://brainly.com/question/12461081
