What is the answer to (r+6)/5 =(r+8)/7 ?

The answer to (r+6)/5 =(r+8)/7 is r=-1

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(r+6)/5 =(r+8)/7

\frac{r + 6}{5} = \frac{r + 8}{7}

r = - 1

Solution steps

\frac{r + 6}{5} = \frac{r + 8}{7}

Apply fraction cross multiply: if

\frac{a}{b} = \frac{c}{d}

then

a \cdot d = b \cdot c

(r + 6) \cdot 7 = 5 (r + 8)

Expand

(r + 6) \cdot 7 : 7 r + 42

Expand

5 (r + 8) : 5 r + 40

7 r + 42 = 5 r + 40

Move

42

to the right side

7 r = 5 r - 2

Move

5 r

to the left side

2 r = - 2

Divide both sides by

2

r = - 1

k^{2} - 5 k = k + 7

6 x^{2} y - 28 x y + 30 y

14 = x 2

\frac{- 4 w ^{- 4} x ^{3}}{12 w ^{5} x ^{- \frac{1}{8}}}

\frac{1}{9} π