Suki SP14
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Hi Sookie, the picture you sent me is not the same as the link
that you sent so and this is very hard to see but I believe
this says the point to six nine and X + 7 Y equal 4.
Now the actual problem that you sent the link for was 6-8 and X
+ 2 Y equals 7.
So if we look at this one, we want it to be parallel.
So the first thing we need to do is we take this line and we have
to solve for Y in order to get the slope.
So we're going to subtract X from each side and we get 2Y
equaling negative X + 7.
Then we're going to divide by two, SO two y / 2.
This negative X is really understood to be a -1, so we
could think of it as -1 half X + 7 halves.
So we get Y equal -1 half X + 7 halves.
So the slope here is negative 1/2, and the fact that we want
it parallel means we're going to keep the negative 1/2 exactly
the way it is.
If it had said perpendicular, we'd use the negative
reciprocal.
So now it's going to be point slope form y -, 8 equaling
negative 1/2 times the quantity X -, 6.
So the first thing we're going to do is distribute.
So we're going to get negative 1/2 * X minus negative 1/2 * 6.
There are a lot of ways to think about this.
You could think of it as -6 times negative 1/2, you could
think of it as negative 1/2 * -6 or you could think of it as
negative negative 1/2 * 6.
If we do all of these, we're actually going to get the same
answer.
Negative times a negative is going to be a positive, Negative
times a negative again is a positive and the opposite of a
negative is a positive.
So what we really need to do is we need to think of that 6 is
over 1.
So 6 / 1 * 1 / 2 would give us 6 / 2 or three.
If we did this 1/2 * 6, that 6 is still over one.
We multiply the numerators and we multiply the denominators.
We get 6 / 2 is 3.
So 1/2 * 6 / 1, 6 / 2 or 3.
So this turns into y - 8 equaling negative a half X + 3.
So we get Y equal -1 half X + 11.
When we add the 8 to each side, add 8 to one side, we're going
to add 8 to the other.
So Y equal negative a half X + 11.
So if we go back to the equation Y equal -1 half X plus Y equal
-1 divided by two X + 11, and then, oh, that was all of the
problems.
So that's how we do that particular problem.
The picture that you had sent me had that might have been a nine,
but that's OK.
We would start it the same way.
So we'd have the seven Y equaling negative X + 4.
We would divide by 7, so we get Y equal -1 seventh X + 4
sevenths.
Now it's parallel, so we just take this -1 seventh and this
looks good here.
Y - 9 equaling -1 seventh X - 6.
It may be that there's a negative missing.
Once again, it's hard for me to see in this picture.
So the negative 1/7 * X would be if this has a negative with it
-1 seventh X and then this -6.
Think of it as -6 / 1.
So we get negative 1/7 * -6 / 1.
Multiply the tops, multiply the bottoms.
So we're going to get plus 6 sevenths.
It looks to me like you were multiplying by 7 / 7, which is
equivalent to one.
But here we're actually doing the distributive property the -1
seventh times and the -6 times.
So then if we have the Y -, 9, we're going to add the nine
across.
So we're going to have Y equaling -1 seventh, X + 6
sevenths +9.
Now this 9 has to get a common denominator to add with the
seven.
So this is an example where we do multiply by 7 / 7 so we can
add these two terms so that nine is understood over 1.
So this turns into 63 sevenths plus the 6th sevenths we already
had.
So our final should be Y equal -1 seventh X plus.
Whoops, I wrote that backwards.
Y equal -1 seventh X + 63 and six is 69 sevenths.
Hopefully this helps.