Given the expressions [tex]$3x, (-2x), y$[/tex] and [tex](-3y)$[/tex], answer the following questions.

a) What are the like terms in these expressions?

b) Find the product of these expressions.

c) Find the sum of these expressions and multiply the sum by [tex]$(x + 2y)$[/tex].



Answer :

Let's carefully analyze and solve the given problem step-by-step.

Given expressions are [tex]\(3x\)[/tex], [tex]\(-2x\)[/tex], [tex]\(y\)[/tex], and [tex]\(-3y\)[/tex].

### a) Like terms
Like terms are terms that have the same variable raised to the same power.

- [tex]\(3x\)[/tex] and [tex]\(-2x\)[/tex] are like terms because both have the variable [tex]\(x\)[/tex].
- [tex]\(y\)[/tex] and [tex]\(-3y\)[/tex] are like terms because both have the variable [tex]\(y\)[/tex].

So, the like terms are:
[tex]\[ (3x, -2x) \][/tex]
[tex]\[ (y, -3y) \][/tex]

### b) Product of these expressions
To find the product of these expressions, we multiply all the coefficients together and write the variables with their respective powers.

- Coefficients: [tex]\(3\)[/tex], [tex]\(-2\)[/tex], [tex]\(1\)[/tex] (coefficient of [tex]\(y\)[/tex]), and [tex]\(-3\)[/tex]

Let's multiply the coefficients:
[tex]\[ 3 \times (-2) \times 1 \times (-3) = 18 \][/tex]

Now, let's consider the variables:
[tex]\[ x \times x = x^2 \][/tex]
[tex]\[ y \times y^{-1} \times y = y^{-1} y = y^0 = 1 \][/tex]

So, the product of these expressions is:
[tex]\[ 18 \][/tex]

### c) Sum of these expressions and multiply the sum by [tex]\((x + 2y)\)[/tex]
First, let's find the sum of the given expressions:

[tex]\[ 3x + (-2x) + y + (-3y) \][/tex]

Combine the like terms:
[tex]\[ 3x - 2x = x \][/tex]
[tex]\[ y - 3y = -2y \][/tex]

Thus, the sum of the expressions is:
[tex]\[ x - 2y \][/tex]

Next, we need to multiply this sum by [tex]\((x + 2y)\)[/tex]:

[tex]\[ (x - 2y)(x + 2y) \][/tex]

We use the distributive property (FOIL method):
[tex]\[ x(x) + x(2y) - 2y(x) - 2y(2y) \][/tex]

Simplify each term:
[tex]\[ x^2 + 2xy - 2xy - 4y^2 \][/tex]

Combine like terms:
[tex]\[ x^2 + 0 - 4y^2 = x^2 - 4y^2 \][/tex]

Therefore, the result of multiplying the sum by [tex]\((x + 2y)\)[/tex] is:
[tex]\[ x^2 - 4y^2 \][/tex]