Question

2a) If a+b= 7 and ab=10 find a-b

Answer 1

Answer:

Step-by-step explanation:

a+b=7

a=7-b

ab=10

7-b(b)=10

7b-b^2=10

-b^2+7b-10

b^2-7b+10

(b-5)(b-2)

b=5,2

a=7-b

a=7-5.         a=7-2

a=2.             a=5

a-b=5-2.        a-b=2-5

   =3.                 =-3

a-b=plus or minus 3