Question

if a+b= 5, find the value of
(1)a square+b square
(2)a-b

Answer 1

for 2 variable we need 2 equations
in this case
a may be 1,2,3,4
and
b can be
1,2,3,4

Answer 2

(1) Given a+b= 5 Taking square both the sides : (a+b)^2= 25 a^2+b^2+2ab= 25 a^2+b^2= 25-2ab (2) a+b= 5 Add and substract b a+b-b+b= 5 a-b= 5-2b