What is the answer to 2/(r+4)= 4/r ?

The answer to 2/(r+4)= 4/r is r=-8

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2/(r+4)= 4/r

\frac{2}{r + 4} = \frac{4}{r}

r = - 8

Solution steps

\frac{2}{r + 4} = \frac{4}{r}

Cross multiply

2 r = 4 r + 16

Move

4 r

to the left side

- 2 r = 16

Divide both sides by

- 2

r = - 8

Verify Solutions

Find undefined (singularity) points:

r = - 4, r = 0

Combine undefined points with solutions:

r = - 8

x + \frac{1}{x} = 45

N, T + \frac{a}{N} = F

\frac{x}{x + 2} = \frac{3}{2}

\frac{3}{3 b + 4} = \frac{2}{b - 4}

I, R = \frac{E}{I}