The problem is to expand the expression $(2x - y)(x + 3y)$.

1. Problem Description

The problem is to expand the expression $(2x - y)(x + 3y)$.

2. Solution Steps

To expand the expression $(2x - y)(x + 3y)$, we can use the distributive property (also known as the FOIL method).

$(a + b)(c + d) = a*c + a*d + b*c + b*d$

Applying the distributive property, we have:

$(2x - y)(x + 3y) = (2x)(x) + (2x)(3y) + (-y)(x) + (-y)(3y)$

Now, we simplify each term:

$(2x)(x) = 2x^2$

$(2x)(3y) = 6xy$

$(-y)(x) = -xy$

$(-y)(3y) = -3y^2$

So, we have:

$2x^2 + 6xy - xy - 3y^2$

Combine the like terms:

$6xy - xy = 5xy$

Therefore, the expanded expression is:

$2x^2 + 5xy - 3y^2$

3. Final Answer

$2x^2 + 5xy - 3y^2$