Dada a função de duas variáveis definida por f(a+b,a-b)=2×+4y/2×-y?

  Portanto: x + y = 47 y = 47 – 29 y = 18 Resposta: Rodrigo acertou 29 arremessos e errou 18. x y x y x y x y x x + = − = +    + + = − =      = = 195 72 13 195 85 2 280 140 x y x y x y x y x y x y + = ⋅ − − = +    − = − ⋅ − =    + − + = − = − 6 3 6 14 14 3 24 28 3 24 1 ( ) ( ) 28 2 52 26     = = y y x y x y x y x y x x + = − =    + + = − =     = = 47 7 3 149 3 3 141 7 3 149 10 290 29 · ( )