Question

Responda 7×+8y=23
×+Y=5

Answer 1

 7x + 8y = 23
 x + y = 5   → x = 5 - y

7( 5 - y ) + 8y = 23

35 - 7y + 8y = 23

y = 23 - 35

y = - 12  resposta


x + y = 5

x - 12 = 5

x = 5 + 12

x = 17  resposta