# If Equations #x^2+ax+b=0# & #x^2+cx+d=0# have a common root and first equation have equal roots,solve Then prove that 2(b+d)=ac How to prove?solve

##### 1 Answer

Apr 25, 2017

see below

#### Explanation:

note:

for this problem we will use the property of the sum and product of roots of a quadratic

that is

if

then

let the common root be

for eqn

for the eqn

then