Question

4) Sabendo que x² + y² = 8 e que 2xy = 22, calcula (x + y)²

Answer 1

$\begin{array}{l}x^{2} +y^{2} =8\\\\\Longrightarrow x^{2} +y^{2} +2xy=8+2xy\\\\\Longrightarrow ( x+y)^{2} =8+2xy\\\\\text{Mas\ } 2xy=22\\\\\therefore \boxed{\boxed{( x+y)^{2} =8+22=30}}\end{array}$

Answer 2

Resposta:

Explicação passo a passo:

$(x+y)^{2} =x^{2} +2xy+y^{2}$

$(x+y)^{2} =(x^{2} +y^{2})+2xy$

$(x+y)^{2} =8+22$

$(x+y)^{2} =30$