Which property would be useful in proving that the product of two rational numbers is ALWAYS rational?
A)
a/b+c/d= ad + bc/bd

B)
a + b/cd= a/cd+ b/cd

C)
a/b· c/d= ac/bd

D)
a/b÷ c/d= a/b· d/c

Question

Which property would be useful in proving that the product of two rational numbers is ALWAYS rational?
A)
a/b+c/d= ad + bc/bd

B)
a + b/cd= a/cd+ b/cd

C)
a/b· c/d= ac/bd

D)
a/b÷ c/d= a/b· d/c

anonymous · Answer

do you know how to add fractions?

anonymous · Answer

only one of those answers is the way to add fractions, the other three are not

anonymous · Answer

oh ok

mathstudent55 · Answer

@satellite73 
The question deals with the product of rational numbers, not the sum.

anonymous · Answer

oooh !! so it does!

acxbox22 · Answer

:OOOOO

anonymous · Answer

my mistake
pick the one that shows how to multiply fractions then

mathstudent55 · Answer

If numbers a, b, c, and d are integers, then any fraction with these numbers as numerator and denominator is a rational number with the exception of zero in the denominator which is not defined.

anonymous · Answer

funny i was wondering why the answer wasn't C, because it is always C

anonymous · Answer

lol its C

anonymous · Answer

turns out it is still C even though i thought it was A
silly me

mathstudent55 · Answer

When you multiply two such fractions, you get an integer in the numerator and an integer in the denominator, so the product is also a rational number.

anonymous · Answer

suppose the denominator is $\pi$?

anonymous · Answer

ir'll be irational

anonymous · Answer

just kidding relax

anonymous · Answer

*it'll

mathstudent55 · Answer

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thesmartone · Answer

Satellite made a mistake :o

But MathTeacher (yes, he should a math teacher) was there to the rescue. :D

mathstudent55 · Answer

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