00:01
So this is a word problem involving a right angle.
00:05
The word problem itself, after you read through it, outlines the looks of the right triangle that is to be created.
00:15
So when reading the word problem, you are given a leg right here that will be called x.
00:24
Consecutive integers will create this triangle.
00:28
And consecutive integers, we know 3, 4, 5, 6, 7, those are consecutive.
00:32
Each number is one greater than the number before it.
00:38
So there's the first consecutive integer after x.
00:44
And then the next consecutive integer after x will be an additional one after.
00:50
And there then becomes my hypotenuse.
00:52
How do i know that's my hypotenuse? the green one? i know that because it is the larger of the three numbers.
01:00
Good practice.
01:02
Wrap any by.
01:03
I know meals in parentheses.
01:05
Whenever you are going to have to square those, it becomes much more complex than it looks.
01:13
My right angle is right here.
01:19
So the question is, what are the dimensions of the three legs? so we will have three answers when we're finished.
01:27
Let us go to pythagorean serum, which states that the square sum, which is an addition sign, of the square of the two legs, which we will call a and b, will always be equal to the square of the hypotenuse, which is always c.
01:44
Now, a and b don't matter which order you put in the two legs.
01:49
X is one leg, x plus one is the second leg.
01:54
C does matter.
01:55
It must be the x plus two.
01:58
So when i read left to right, the first leg i see is the x.
02:01
So i'm going to substitute the x in for the a, and i get x squared.
02:07
I'm going to substitute in parentheses, x plus 1 in for b, and i will get the binomial squared.
02:17
This is not as simple as squaring the x and squaring the 1 and calling it x squared plus 1.
02:24
It is not that simple.
02:26
So please remember that.
02:28
We'll get to the foiling of that in just a moment.
02:32
C is x plus 2.
02:33
Again, in parentheses, this is not as simple as x squared plus 4.
02:41
Okay, now my job is to solve for x, but i first must remove all the parentheses.
02:46
And to remove the parentheses, i have to square the binomial.
02:51
So the first term remains x squared.
02:56
I'm going to write out in red everything that comes out of the x plus one.
03:00
We get the x plus, i'm sorry, the x times x, which is x squared, plus x times one, which is one x, times one plus x, which is another one x, plus 1 times 1.
03:16
That is x plus 1 squared right there.
03:18
Four terms.
03:20
Now i'm going to do the same to my x plus 2.
03:23
X times x is x squared.
03:28
X times 2 is 2x.
03:31
2 times x is 2x.
03:35
2 times x is 2x and 2 times 2 is 4.
03:41
There we go.
03:43
So that is my binomial squared being very careful with the squaring of.
03:49
Them.
03:50
Now what i'm going to do is combine like terms on either side.
03:55
What i do see is x squared plus x squared can be combined to become 2x squared.
04:05
Addition means you add the coefficients.
04:08
You don't mess with the exponent.
04:10
I see another set of combinable like terms.
04:14
1x plus 1x again add the coefficient 1 plus 1 is 2.
04:18
Don't mess with the exponent with the x...