8/21=negative 2/7x what is the value of x! explain how and what you do to get the problem so i can learn too
you!

You have to get x alone so you divide -2/7 to 8/21

x = -3/4

8 /21 =  - 2/7x.     

Cross multiply by multiplying both the numerator of one fraction with the denominator of the other fraction., equating it to the other numerator multiplied by the other denominator.

7x*8 = -2*21

x*7*8 = -2*21

x =  -(2*21) / (7*8).              2 into 8 is 4.    7 into 21 is 3.

x =  - 3/4

I hope this helps.