b - 5/b = 4
how do I solve this?
2007-01-30 14:48:54 · 8 answers · asked by Anonymous in Education & Reference ➔ Homework Help
1. find the common denominator between "b" and "5/b" which is "b"
2. make the left side of the equation into one nomial.
the equation would look like this:
(b^2-5)/b=4 (b squared minus five, divided by b equals 4)
3. cross multiply
the equation looks like this now
b^2-5 = 4b
4. subtract 4b from both sides:
b^2-4b-5 = 0
5. create a binomial frm b^2-4b-5:
(b + 1) (b - 5) = 0
6. what answer would make each binomial = 0?
b+1 = 0 (b=-1)
b-5 = 0 (b=5)
7. substitute both values separately into the original equation, see which one works.
8. when you do this, you will find that b = -1 is the right answer.
ok so ive done everything for you, now all you have to do is put it on paper correctly. can i get 10 pts please??
2007-01-30 15:03:44 · answer #1 · answered by alleleone81 2 · 0⤊ 0⤋
Is it (b-5)/b or b-(5/b).
For (b-5)/b=4 u would cross multiply, changing 4 to 4/1.
So then u would have b-5=4b. Subtract b from both sides and solve for the variable as u normally would.
2007-01-30 22:59:04 · answer #2 · answered by Anonymous · 0⤊ 0⤋
1. Multiply both sides by b to eliminate the fraction:
(b-5/b)*b = 4*b
b-5 = 4b
2. Put all variables on the same side, so subtract b from each side of the equation
b-5 -b = 4b -b
-5 = 4b - b
3. Simplify.
-5=3b
4. divide both sides of the equation by 3
-5/3 = 3b/3
-5/3 = b
5. Check your answer!
[(-5/3)-5] / (-5/3) = 4
(-20/3) / (-5/3) = 4
4 = 4 --> We are right!
2007-01-30 23:01:33 · answer #3 · answered by Paige 3 · 0⤊ 0⤋
You may or may not have a quadratic depending on whether that's
(b - 5)/b = 4
or
b - (5/b) = 4
Either way, the advice from the two posters above will solve it. You do have to remember that the solution b = 0 is not possible. It won't happen here, but if you ever get a solution that would make the denominator 0, you have to reject it.
2007-01-30 22:55:45 · answer #4 · answered by Anonymous · 0⤊ 0⤋
b= -5\3 b-5\b=4 multipy both by b b-5=4b -5=3b -5\3=b
2007-01-30 22:56:40 · answer #5 · answered by harashteb 1 · 0⤊ 0⤋
Multiply both sides by b and then you have a quadratic. You probably already know all about the quadratic formula, so this should be easy.
2007-01-30 22:53:41 · answer #6 · answered by Charles Fahringer 3 · 0⤊ 0⤋
b-5/b = 4
cross multiply these two terms
then solve it
see this picture i wrote it down for you
http://img408.imageshack.us/img408/1058/20070130383fh6.jpg
2007-01-30 23:00:13 · answer #7 · answered by Anonymous · 0⤊ 0⤋
multiply both sides by b.
then continue.
2007-01-30 22:53:34 · answer #8 · answered by Gruntled Employee 6 · 0⤊ 0⤋