Дан фрагмент программного кода. Определите значение переменной Y
после выполнения этих операторов.

…
X = 16;
Y = 14;
if (X > Y) Y = X + 2;
else Y = Y * 3;
…

Y =

x

2

+

y

2

=

16

...

...

...

...

...

...

.

.

(

1

)

x + y = 4 (2)

rearrange (2) to y = 4 - x (could do x = 4 - y )

substitute y = 4 - x into (1)

hence:  

x

2

+

(

4

−

x

)

2

=

16

⇒

x

2

+

16

−

8

x

+

x

2

=

16

and  

2

x

2

−

8

x

+

16

−

16

=

0

⇒

2

x

2

−

8

x

=

0

factor and solve : 2x(x - 4 ) = 0  

⇒

x

=

0

,

x

=

4

substitute these values into y = 4 - x , to find corresponding values of y.

x = 0 : y = 4 - 0 = 4 → (0 , 4)

x = 4 : y = 4 - 4 = 0 → (4 , 0 )

These are the points of intersection with the line x +y = 4 and the circle  

x

2

+

y

2

=

16

Answer link

Объяснение: