Question

Exercitiul 4, va rog, URGENT, dau coronita!!!!

Answer 1

$x + y = 5$

${x}^{2} - {y}^{2} = - 15$

$(x - y)(x + y) = - 15$

$(x - y) \times 5 = - 15 \: | \div 5$

$x - y = - 3$

$a = x - y + {(x - y)}^{2} + {(x - y)}^{3}$

$a = - 3 + {( - 3)}^{2} + {( - 3)}^{3}$

$a = - 3 + 9 - 27$

$a = - 21$