Question

Sendo x+y=5 e x-y=4, calcule o valor de
${x}^{2} - {y}^{2}$
​

Answer 1

Resposta:

x = 9/2. y = 1/2

| X + y = 5

+ | x - y = 4

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2x = 9

x = 9/2

9/2 + y = 5

y = 5 - 9/2

y = 1/2