I have a question how is my answer wrong I got 2/21 for this equation but I keep getting a warning it is incorrect.

Question

anonymous · Answer

For what question?

anonymous · Answer

equation: 7/3 + -5/7 put into simplest form

aripotta · Answer

7/3 - 5/7

first find the LCD

anonymous · Answer

21

anonymous · Answer

I got 2/21 i keep being told it's wrong do you have any suggestions as of why?

aripotta · Answer

so (7 * 7)/(3 * 7) - (5 * 3)/(7 * 3) = 49/21 - 15/21 = 34/21

anonymous · Answer

7/3 + -5/7 is the same as 7/3 - 5/7
These two need a common denominator, the lowest is 21 so the new equation is:
49/21 - 15/21 
Leave the denominator the same, but suptract the top (49-15=34)

The answer is 34/21 (1 13/21)

anonymous · Answer

ohhh

anonymous · Answer

lol I forgot to do the top part heh now I see what went wrong thank you both :)

aripotta · Answer

no problemo~