Question

If × =2/3 and x=3 are the roots of the quadratic eq ax^2 +7x +b =0 find a and b

Answer 1

Answer: if one of the zero is x=2/3 and x=-3 then

Step-by-step explanation:

  alpha + beta     = 2/3+(-3)      

                           = 2+(-9)/3                    

                           =-7/3      ( equation 1 )

sum of roots      = -7/a     ( equation 2 )

eq 1 in  eq2 =

-7/3 = -7/a

= - 7 cancel out

then a=3

   alpha*beta     =  2/3*(-3)

                          = -2           ( equation 3 )

product of the zeroes

                          = b/a

                          =b/3           ( equation 4 )

                         

eq 4 in eq 3

-2 = b/3

that is, b = -6

hope its clear

if yes pls mark me