Question

Daca x-y=11 si x patrat-y patrat=297 atunci x+y egal cu cat?

Answer 1

$x - y = 11$

${x}^{2} - {y}^{2} = 297$

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

$(x - y)(x + y) = 297$

$11(x + y) = 297 \: | \div 11$

$x + y = 27$

Answer 2

xpatrat - ypatrat = (x+y)(x-y)
297=(x+y) • 11
x+y=297:11
x+y=27
Bafta!