Question

if a+b = 7 and. ab=10 find a-b
plz​

Answer 1

Answer:

a=7-b

ab=10

(7-b) b=10

-b²

Answer 2

Given, (a+b)=7, ab=10

Squaring both sides

⇒(a+b) ^2 =7 ^2

⇒a ^2 +b ^2 +2ab=49

⇒a ^2 +b ^2

=49−2(10)

⇒a ^2 +b ^2

=29

Now,

(a−b) ^2

=a ^2 +b ^2 −2ab

=29−2(10)

=29−20

=9

∴a−b=9^1/2 =±3