Write the given phrase as an algebraic expression. Use the variable x to represent the unknown number.

1 answer:

5 0

Hello! I would love to help!

Let's start with this part of the equation: "the sum of a number and seven"

Alright. We know that x represents an unknown number. Do you see a part of the equation that could translate to "an unknown number?"

I see "a number." So let's fill X in for "a number.

Alright. So now we have "the sum of x and 7."

Next, let's remember that sum means adding. So we just need to 7 to x

X+7

So, now instead of "the sum of a number and 7" we have x+7.

Alright. Now we just have to do the "twice." When it is asking for "twice", it is asking us to multiply our answer by two. But we need to multiply both x and 7. The best way to do that is to put our "x+7" in parenthesis and put a two outside.

2(x+7)

That's your answer! 2(x+7)

Hope this helped! Comment if you have any questions!

You might be interested in

Which is the following statements is NOT true?

Dominik [7]

Answer:

The last one is the answer; The slope of AB is different than the slope of BC.

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

Wyatt estimates that it will cost $425,000 to send his daughter to a private college in 18

Feliz [49]

Interest = p times R times T

7 0

3 years ago

Factor the polynomial, x2 + 5x + 6

patriot [66]

Answer:

Choice b.

$x^{2} + 5\, x + 6 = (x + 3)\, (x + 2)$ .

Step-by-step explanation:

The highest power of the variable $x$ in this polynomial is $2$ . In other words, this polynomial is quadratic.

It is thus possible to apply the quadratic formula to find the "roots" of this polynomial. (A root of a polynomial is a value of the variable that would set the polynomial to $0$ .)

After finding these roots, it would be possible to factorize this polynomial using the Factor Theorem.

Apply the quadratic formula to find the two roots that would set this quadratic polynomial to $0$ . The discriminant of this polynomial is $(5^{2} - 4 \times 1 \times 6) = 1$ .

$\begin{aligned}x_{1} &= \frac{-5 + \sqrt{1}}{2\times 1} \\ &= \frac{-5 + 1}{2} \\ &= -2\end{aligned}$ .

Similarly:

$\begin{aligned}x_{2} &= \frac{-5 - \sqrt{1}}{2\times 1} \\ &= \frac{-5 - 1}{2} \\ &= -3\end{aligned}$ .

By the Factor Theorem, if $x = x_{0}$ is a root of a polynomial, then $(x - x_0)$ would be a factor of that polynomial. Note the minus sign between $x$ and $x_{0}$ .

The root $x = -2$ corresponds to the factor $(x - (-2))$ , which simplifies to $(x + 2)$ .
The root $x = -3$ corresponds to the factor $(x - (-3))$ , which simplifies to $(x + 3)$ .