Question

find the value of x2+y2 when x=4 and y=25. option a 64 b 625 c 29 d 21
​

Answer 1

Answer:

Step-by-step explanation:

x  

2

+y  

2

=25,xy=12

Substitute y=  

x

12

​  

, we get

⇒x  

2

+[  

x

12

​  

]  

2

=25⇒x  

4

+144−25x  

2

=0

⇒(x  

2

−16)(x  

2

−9)⇒x  

2

=16 and x  

2

=9

⇒x=±4 and x=±3

∴ Total number of values of x is 4.