Question

If one zero of the polynomial 3x2+8x+k is -2 then find the value of k

Answer 1

put the value in place of x we get -12-16=-k=-28=-k=so k=28

Answer 2

If -2 is zero of polynomial then if we put the value of x=-2 then it must be equal to zero

3x^2+8x+k=0

3X(-2)^2 + 8(-2) + k = 0

3X4 + (-16) + k = 0

12-16+k=0

-4 + k = 0

k = 4

x represnt x as variable

X represent multiplication sign