If a+b=9 a-b then ab=?
Answers
Answered by
0
a-b=8
a=8+b…….(1)
ab=9
put value of a in above eq
(8+b)b=9
b²+8b-9=0………..[quad eqn]
i.e b²+9b-b-9=0
b(b+9)-1(b+9)=0
(b-1)(b+9)=0
∴ b-1=0 or b+9=0
b=1 or b=-9
if b=1 then ,
a-b=8
a-1=8
a=8+1
a=9
∴a+b=9+1
a+b=10
and if b=-9 then,
a-b=8
a+9=8
a=8–9
a=-1
∴ a+b=-1–9
a+b=-10
∴ the given problem have two solutions
a+b=10
or
a+b=-10
CAN YOU PLEASE MARK MY ANSWER AS BRAINLIEST IT WILL HELP ME A LOT.
Similar questions