Answer:
r = -3/7.
Step-by-step explanation:
To solve this equation, we multiply both sides by 6/7. This is the reciprocal of the coefficient in r (7/6) and will "cancel out" the expression. So:
-1/2 x 6/7 = -6/14 = -3/7.
As such, r = -3/7.
I hope this helps!