Question

x+y=22

4x+2y=74

então calcule o valor de x2+y=?

Answer 1

{x+y=22 ----> x = 22-y ------(I)
{4x+2y=74 --> 4x = 74 -2y --> x = $\frac{74-2y}{4}$ ---(II)
 
 (I) =(II)
 22-y =   $\frac{74-2y}{4}$ ---mmc=4
 88 - 4y = 74 - 2y
 14 = 2y ---> y = 7

(I) x = 22 - y ---> x = 22 - 7 ---> x = 15

calcule o valor de x²+y= 15² + 7 = 225 + 7 = 232