Question

the coefficient of x in quadratic equation x2+px+q=0 was taken as 17 in place of 13 and its roots were found to be -2 and -15 find the roots of original equatjon

Answer 1

Answer:

-10,-3

Step-by-step explanation:

if coff of x replace from 13 to 17 and its roots found to be -2&-15

then,

x^2+17x+q=0

if x=-2

-2^2+17×-2+q =0

4-34+q=0

-30+q=0

q=30

now original eq

x^2+13x+30=0. (put value of q)

by quadratic formula

D=b^2-4ac. a=1,b=13,c=30

=13^2-4×1×30

=169-120

=49

x=(-13+7)÷2. , =(-13-7)÷2

=-6÷2. , =(-20)÷2

=-3. , =-10

roots are (-3,-10)