Question

Can anyone help me please?
Which expression will simplify to 1?
a. (m+9)/(m-9) * (m+9)/(m-9)
b. (m+9)/(m-9) * (m-9)/(m+9)
c. (m+9)/(m-9) * (9+m)/(9-m)
d. (m+9)/(m-9) * (9-m)/(9+m)

Answer 1

Hint \(\Large \frac{a}{b} \times \frac{c}{d} = \frac{ac}{bd}\)

If by chance we have

\(\Large \frac{a}{b} \times \frac{b}{a} = \frac{ab}{ba} = \frac{\cancel{a}\cancel{b}}{\cancel{b}\cancel{a}} = 1\)

Answer 2

So it would be b because '(m+9)/(m-9) * (m-9)/(m+9)' would cancel out (if i did the math correctly)

Answer 3

yeah it's b

Answer 4

GRACIAS AMIGOS! (Thank You 'Friends')

Answer 5

Not a problem!