00:01
Okay, so here's two different situations.
00:03
The top situation, we have two different things that are comparing that are both expressions.
00:08
A mathematical expression is a collection of numbers, operations, and symbols, and variables.
00:14
Okay? that's it.
00:16
That's all it is.
00:18
So two times the quantity of 3x plus 5 is an expression.
00:22
6x plus 10 is an expression.
00:25
These two expressions happen to have the same value.
00:28
They are equivalent expressions.
00:30
Two expressions that have the same value are equivalent expressions.
00:33
No matter what value you plug in for x, you can put any value you want for that variable.
00:38
Doesn't matter.
00:40
These two expressions are going to have an equivalent.
00:43
Like if you plug in a zero for x, then you would have the value over here of two times the quantity of five.
00:50
And over here you have the quantity of just 10, right? well, guess what? two times five is 10.
00:55
So the value is the same.
00:56
So if you plug in a zero for x, you're going to get the same value in both expressions.
01:00
If you plugged in any number for x, you'd get the same value for both expressions because these are equivalent expressions.
01:07
In other words, they are expressions that have the same value.
01:12
When you're talking about this situation down here, these are equivalent equations.
01:17
You can't just plug in any value for x and it will work.
01:21
It's not going to work.
01:22
If i plug in a 7, for example, 2 times 7 is 14, 14 plus 4 is 18.
01:27
18 does not equal 10.
01:29
So a 7 makes a false statement here.
01:31
And it also makes a false statement here.
01:33
7 plus 2 is 9, not 5.
01:36
So when you have an equation, an equation is two expressions that are set equal, right? this is an expression.
01:42
This is an expression...