9)=0 Û X = 2 (0,75Đ)9 =2 Û (2 – X) (17+17 +11− X+ THAY X = 2 Þ X+169 =Y −2516 =Z+925 = X+Y+Z9+16+25=2+169 =2 (1Đ)+ Þ X + Y + Z = 100 (0,25Đ)

9 ) - DE THI HOC SINH GIOI TOAN 7 VA DAP AN THAM KHAO
Toán DE THI HOC SINH GIOI TOAN 7 VA DAP AN THAM KHAO

9

)

=0

Û x = 2

(0,75đ)

9

=2

Û (2 – x)

(

1

7

+

1

7

+

11

− x

+ Thay x = 2 Þ

x

+16

9

=

y −25

16

=

z+

9

25

=

x+

y

+z

9+16+25

=

2+16

9

=2

(1đ)

+ Þ x + y + z = 100

(0,25đ)