Question

if a-b=5 and ab=6 find the value of a+b

Answer 1

let's solve it
squaring both side

(a-b)^2 = 5^2

= a^2 + b^2 -2ab = 25
a^2 + b^2 = 25+ 2ab
a^2 + b^2 = 25 + 12
a^2 + b^2 = 37. .......................1

squaring both side

(a+b)^2 = a^2 + b^2 + 2ab
put the value

(a+ b)^2 = 37+12
(a+b)^2 = 49
(a+b) = √49
a+b = 7

hope its help