Question

if a+b =5 and a-b=2 , find the value of a²+b²​

Answer 1

square the both given equations first...then

a square +b square +2ab = 25
a square +b square - 2ab = 4

then add both the equations and then the result will be...
2(a square + b square) = 29
therefore
a2 +b2 = 29/2

Answer 2

a+b= 5

a-b= 2

using elimination method we get

a=7/2

b=3/2

then value of a^2+b^2=58/4 or 29/2