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7th grade
Course: 7th grade > Unit 6
Lesson 3: Interpreting linear expressionsInterpreting linear expressions: flowers
Let's practice matching expressions to their meaning in this example of interpreting linear expressions. Created by Sal Khan.
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- why don't the videos match what the questions are talking about in the actual practice lesson?(11 votes)
- This video uses the actual practice lesson. The format looks different because it is the old format that KA had until a couple of years ago. But the problems do come from the exercise set.(4 votes)
- This video is so confusing that I feel brain dead like Kaminari...somone explain this more simple to me so I don't fry my brain with electric from my headphones because they are dead...(10 votes)
- Thanks for advice. And at least someone understood my joke...I'm just trying to lighten up the mood with comedy from My Hero Academia..And I was trying to be funny, I like making jokes like that.(5 votes)
- What is a linear expression?\(4 votes)
- "It is made up of two expressions set equal to each other. A linear equation is special because: It has one or two variables. No variable in a linear equation is raised to a power greater than 1 or used as the denominator of a fraction."
For more information and reference go here:
http://eduplace.com/math/mathsteps/7/d/index.html(1 vote)
- I don't understand why you didn't use 3(3t+4v) isn't it the same, just distributed backwards?(1 vote)
- It's because 4 tulips (4T) and 3 violets (3V) is not the same thing as 3 tulips and 4 violets(4 votes)
- this isnt helping at all(2 votes)
- Well, it makes sense. Variables also have several unknowns. But it's one of each. 2V + V
V in this case is equal to 1. So the solution is 3V.
And remember the video before. The variable means 1V. V can be anything.(2 votes)
- Solve the equation for x
5x squared minus 4x =6(1 vote)- I'll assume you mean 5x² - 4x = 6.
First thing to do is to carry the 6 to the left side of the equal sign; 5x² - 4x - 6. Then you factor; in this case, you cannot, so use the quadratic formula and you'll be able to find your x. I hope this will help!(2 votes)
- How did you get 4T + 3V?(1 vote)
- 4T = 4 tulips
3V= 3 violets
4T + 3V = 1 buoquet, as stated in the video.(1 vote)
- i dont get anything tho :((1 vote)
- Someone please help! The format of the problem changed and I have problems converting what he said to my problem!(0 votes)
- i dont understand the video can someone help me?some of the problems we get are hard and look nothing like this.(2 votes)
Video transcript
Martin likes to
make flower bouquets that each have 3
violets and 4 tulips. If the price of a violet is V
and the price of a tulip is T, match the expressions
to their meanings. So let's see-- the price
of 1 of Martin's bouquets. So one of Martin's bouquets
has 3 violets and 4 tulips. So the 3 violets are
going to cost 3 times the price of the
violet, which is V. So that's the cost of
the violets, 3V. And then the 4 tulips
are going to cost 4 times the price of a tulip. So that's 4T. So it's 3V plus 4T. So it's not this one. Let's see. This one right over
here, this is 4T plus 3V. So this is the price of 4
tulips, 4 times the price of a tulip, plus 3 times
the price of a violet. The price of 3 of
Martin's bouquets, so it's essentially going
to be 3 times this quantity right over here. This is the price of 1 bouquet. We want 3 of them. So it's going to be 3 times
the quantity 4T plus 3V. And let's see. If I were to actually multiply
this out, 3 times 4T is 12T, and then plus 3 times 3V is 9V. So this is the same
thing if I were to distribute the
3-- is 12T plus 9V. Well, that's this
right over here. These two are
equivalent expressions. And let's see. Are any of these other
things equivalent? No, this says 3
times 3T plus 4V. So I'm going to put this
in the not used bucket. And then I have--
let's see-- 3V plus 2T. I'm going to put it in
the not used bucket. And let's see. This has 2V plus 4T plus V.
So if I were to simplify this, if I were to combine the V
terms-- if I have two V's and I add another V, that's
three V's plus 4T. So this is actually the
same thing as the price of 1 of Martin's bouquets. So you could view this
as the price of 2 violets plus the price of 4 tulips
plus another violet. So it's really the price
of 3 violets and 4 tulips. So let's check our answer. We got it right.