yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Writing expressions with parentheses | 6th grade | Khan Academy


2m read
·Nov 10, 2024

We have two different statements written in English that I would like you to pause this video and try to write as an algebraic expression.

All right, now let's work on this first one. So you might be tempted to say, "All right, I have five, so let me just write a five times," and I'll write a dot because when we're dealing with algebra, if you write a traditional multiplication sign, it can get confused with an x.

Five times the difference of x and two. The difference of x and two we could write as x minus, but this expression has a problem because whoever's interpreting it, if they're following order of operations (which they should), that would mean that they would multiply the 5 and the x first and then subtract 2.

But that's not what's going on in the sentence. It's 5 times, not x, but the difference of x and 2. So what you need to do is put parentheses here to make sure that you take the difference of x and 2 first and then multiply that by 5.

Now, with that in mind, let's tackle this example right over here: 10 times the sum of y and 3. Well, once again, if you just wrote 10 times the sum of y and 3, you'll run into the same problem. Someone would interpret this as, "Hey, maybe I should multiply 10 and y first because that's what order of operations would tell me to do."

But that's not what we want. We want 10 times, not just y, but the sum of y and 3. So that's where the parentheses are really important to make sure that we take the sum of y and 3 first and then multiply that by 10.

More Articles

View All
How to Apply and Succeed at Y Combinator by Dalton Caldwell
Okay, what we’re going to talk about today is how to apply and succeed at YC. In my capacity as the head of admissions, I go around the world, and I give talks, and I meet folks that are applying, and I answer lots of questions. So I think I have a decent…
Sampling distribution of the difference in sample means | AP Statistics | Khan Academy
What we’re going to do in this video is explore the sampling distribution for a difference in sample means, and we’ll use this example right over here. So it tells us a large bakery makes thousands of cupcakes daily in two shifts: shift A and shift B. Su…
Why you're always tired
One of the most common problems I hear about nowadays, and I’m sure everyone else does, is this feeling of being chronically tired. Because sometimes it feels like no matter how much sleep you get, you just can’t seem to perk up, feel energetic for most o…
The Global Economic Trends Post-Election | Explorer
Where do you see things now that we’re about a month in? I would actually distinguish between what we actually see in the markets and the story that Wall Street is telling. The story that Wall Street is telling is all optimistic. We’re going to have all …
'Pirate Birds’ of the Tropics 180 | National Geographic
This wildlife refuge is on a remote windy island between Nicaragua and Costa Rica. It’s dedicated to protecting seabirds, especially the large populations of brown pelicans and magnificent frigate birds that nest here. Frigate birds have extraordinarily …
Potential energy | Energy | Middle school physics | Khan Academy
Hello everyone! Let’s talk about potential energy. Potential energy is energy that is stored in an object, and this energy is related to the potential or the future possibility for an object to have a different type of energy, like kinetic energy from mo…