Question #dc056

1 Answer
Dec 28, 2017

25

Explanation:

Its given that #x+y = xy = 5#
Now, to solve the given equation which is:
#x^2y+y^2x = ????#

This equation can also be written as:
#x xx x xxy# + #yxxyxxx#

Now, #xy# or #yx# in the above equation can be replaced by #5# (#yx# can also be replaced by #5# because multiplication of numbers in either sequence will give the same answer. For eg: #2xx3=3xx2=6#)

and then, the equation becomes: #5x+5y#

Taking the common factor #5# out, we get #5(x+y)#..........(1)

But #x+y=5#
Putting this value of #x+y# in the equation (1)

or, #5 xx 5 = 25#