Question

If a + b and 5 ab = 2, find the value of a²+ b²

Answer 1

$a + b = 5 \: and \: ab = 2$

${a}^{2} + {b}^{2} = {a}^{2} + {b}^{2} + 2ab$

${a}^{2} + {b}^{2} = {5}^{2} + 2 \times 2$

${ a}^{2} + {b}^{2} = 25 + 4$

${a}^{2} + {b}^{2} = 29$

Answer 2

Step-by-step explanation:

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