Question

considerando x²+y²=125 e x.y=50,qual o valor de (x-y)²

Answer 1

( x - y)² = x² - 2xy + y²  ou
( x² + y²) - 2xy  = 0
substituindo  temos
( 125 ) - 2 ( 50 ) =  125 -  100 = 25 *****