Question

plz solve all the questions ​

Answer 1

${a}^{2} + {b}^{2} = 34 \\ ab = 12 \\ {(a - b)}^{2} = {a}^{2} + {b}^{2} - 2ab \\ = 34 - 2 \times 12 \\ = 34 - 24 \\ = 10 \\ a - b = \sqrt{10 } \\ {(a + b)}^{2} = 34 +24 \\ = 58 \\ a + b = \sqrt{?}$

$\sqrt{58 } = a + b \\ 3 {(a + b)}^{2} + 3 {(a - b)}^{2} = \\ \\ = 3 \times 58 + 3 \times 10 \\ = 174 + 30 = 204 \\ 9 {(a - b)}^{2} - 2 {(a + b)}^{2} = \\ 9 \times 10 - 2 \times 58 \\ 90 - 116 = - 26$