math help??

Question

I can't get how to do this.

1/a + 1/b = 1/c. Solve for C.

Answer 1

1/a + 1/b = 1/c. Solve for C.

Multiply both sides by c.

c(1/a + 1/b) = c(1/c)

Do not distribute the c on the left side.

c(1/a + 1/b) = 1

Now divide both sides by (1/a + 1/b)

c = 1/(1/a + 1/b)

Multiply the top AND bottom of the fraction by the common denominator (a*b)

c = 1(ab)/[ab(1/a + 1/b)]

Distribute on the bottom

c = ab/[ab*(1/a) + ab*(1/b)]

c = ab/(b+a)

Hope that helped
10 pts best answer?

Answer 2

c= a+b

multiply both sides by c. Then divide both sides by 1/a + 1/b. then you have 1/(1/a +1/b) and you'll have to take the reciprocal which is 1(a/1 + b/1) which turns out to be a+b

Answer 3

Ask Dr. Math is a good website to find your answers, or have your questions answered.

http://mathforum.org/dr.math/

http://mathforum.org/students/


Good luck and I hope this helps.

Answer 4

I think this is what you need

1/a + 1/b = 1/c
1/a(c/1) + 1/b(c/1) = 1/c(c/1)
c/a +c/b = c/c
c/a +c/b = 1
2c/(a+b) =1
2c = a+b
c = (a+b)/2

someone confirm this please