Write the given phrase as an algebraic expression. use the variable x to represent the unknown number. twice the sum of a number and seven. the answer is:

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!

I'll do the first one for you. it isn't very hard at all.on number one, you have (50 × 3), which equals 150, and (3 × 3), which equals 9. after you establish that, you add 150 and 9 together. so, (150 + 9) equals 159.this means that 53 × 3 = 159.