Question

Let f(x) = x + 7 and g(x) = x − 4. Find f(x) ⋅ g(x). (1 point)

Answer 1

`\longmapsto f(x) = x + 7 \\ \longmapsto g(x) = x - 4 \\→ f(x)g(x) = (x + 7)(x - 4) \\ = {x}^(2) - 4x + 7x - 28 \\ = \boxed{ {x}^(2) + 3x - 28}✓`

• x²+3x-28 is the right answer.

Answer 2

`f(x)*g(x) = x^2+3x-28`

Explanation:

`f(x) = x+7\\g(x) = x-4\\\\f(x) * g(x) = (x+7) * (x-4)`

To solve a multiplication of 2 parenthesis, we'll multiply each of the terms on the left with each of the terms on the right. Then, add all of the products together.

First, x (left) with x (right):

`x * x = x^2`

Next, x (left) with -4 (right):

`x * (-4) = -4x`

Next, 7 (left) with x (right):

`7 * x = 7x`

Finally, 7 (left) with -4 (right):

`7 * (-4) = -28`

Now we have 4 products. To find the result of the entire expression, we need to add all of these together.

`x^2 - 4x + 7x - 28`

We can simplify -4x+7x to 3x:

`x^2 + 3x-28`

Answer:
`f(x)*g(x) = x^2+3x-28`