# Question dc056

Dec 28, 2017

25

#### Explanation:

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

This equation can also be written as:
$x \times x \times y$ + $y \times y \times x$

Now, $x y$ or $y x$ in the above equation can be replaced by $5$ ($y x$ can also be replaced by $5$ because multiplication of numbers in either sequence will give the same answer. For eg: $2 \times 3 = 3 \times 2 = 6$)

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

Taking the common factor $5$ out, we get $5 \left(x + y\right)$..........(1)

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

or, $5 \times 5 = 25$