SOLUTION: 5/y-3=y+7/2y-6+1 I need help solving this

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Question 173560: 5/y-3=y+7/2y-6+1 I need help solving this
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
5/y-3=y+7/2y-6+1

Hmmm! You didn't put parentheses to show where numerators 
and denominators begin "(" and end ")", so I'm guessing you
mean one of two possibilities.  I'll do both:

If you mean this:

matrix%281%2C5%2C+5%2F%28y-3%29%2C%22=%22%2C%28y%2B7%29%2F%282y-6%29%2C%22%2B%22%2C1%29

Write the 1 as 1%2F1 so every term will
be a fraction:

matrix%281%2C5%2C+5%2F%28y-3%29%2C%22=%22%2C%28y%2B7%29%2F%282y-6%29%2C%22%2B%22%2C1%2F1%29

Enclose each term in parentheses:



Factor the denominator 2y-6 as 2%28y-3%29



Find the LCD, which is 2%28y-3%29, which we will
write as %28%282%28y-3%29%29%2F1%29 and multiply each term
by it:



Cancel what will cancel:



All that's left is:

matrix%281%2C3%2C2%2A5%2C%22=%22%2C+y%2B7%2B2%28y-3%29%29

Distribute:

matrix%281%2C3%2C2%2A5%2C%22=%22%2C+y%2B7%2B2y-6%29%29

Combine like terms:

matrix%281%2C3%2C10%2C%22=%22%2C+3y%2B1%29%29

Add -1 to both sides

matrix%281%2C3%2C9%2C%22=%22%2C3y%29

Divide both sides by 3:

matrix%281%2C3%2C3%2C%22=%22%2Cy%29

Now we must check this answer, by
substituting it into the original, to make sure it
is not an extraneous solution:

matrix%281%2C5%2C+5%2F%28y-3%29%2C%22=%22%2C%28y%2B7%29%2F%282y-6%29%2C%22%2B%22%2C1%29



matrix%281%2C5%2C+5%2F0%2C%22=%22%2C%28y%2B7%29%2F%286-6%29%2C%22%2B%22%2C1%29

matrix%281%2C5%2C+5%2F0%2C%22=%22%2C%28y%2B7%29%2F0%2C%22%2B%22%2C1%29

But since division by 0 is undefined, there is
no solution. 3 was an extraneous, or "bogus"
solution, not an actual solution.

================

If you meant this:



Use 1 denominators so that all terms will be
fractions:



Enclose each term in parentheses:



Factor the denominator 2y-6 as 2%28y-3%29



Find the LCD, which is 2%28y-3%29, which we will
write as %28%282%28y-3%29%29%2F1%29 and multiply each term
by it:



Cancel what will cancel:



All that's left is:



matrix%281%2C7%2C+10%2C%22=%22%2C2y%28y-3%29%2C+%22%2B%22%2C+7%2C+%22%2B%22%2C+2%28y-3%29%29

Distribute to remove parentheses:

matrix%281%2C3%2C10%2C%22=%22%2C2y%5E2-6y%2B7%2B2y-6%29

Collect like terms:

matrix%281%2C3%2C10%2C%22=%22%2C2y%5E2-4y%2B1%29

Get 0 on the left by subtracting 10 from both sides:

matrix%281%2C3%2C0%2C%22=%22%2C2y%5E2-4y-9%29

or, since I like to have 0 on the right, not left,
I'll switch the sides:


matrix%281%2C3%2C2y%5E2-4y-9%2C%22=%22%2C0%29

That doesn't factor, so we use the quadratic
formula:

y+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+



y+=+%284+%2B-+sqrt%2816%2B72%29+%29%2F4+

y+=+%284+%2B-+sqrt%2888%29+%29%2F4+

y+=+%284+%2B-+sqrt%284%2A22%29+%29%2F4+

y+=+%284+%2B-+2sqrt%2822%29+%29%2F4+

Factor 2 out of the numerator:

y+=+%282%282+%2B-+sqrt%2822%29%29+%29%2F4+

Cancel the 2 on top into the 4 on the bottom,
getting 2 on the bottom:

y+=+%28cross%282%29%282+%2B-+sqrt%2822%29%29+%29%2F%28cross%284%29%29%5B2%5D+

y+=+%282+%2B-+sqrt%2822%29+%29%2F2+

This is difficult to check. However if we were
to substitute that in the original, none of the
denominators would be 0, as they were in the
first way I assumed you meant.  So these are both
solutions.

Edwin