Let
Y=the food is yummy
O=overeat
E=exercise
Note:
∪ = or
-> if ... then
(Y∪O)->E
Option A. 150 m 3 is the correct one

First, we combine the terms on the left side of the equation to simplify the equation. Then we divide both sides by -3. k then equals 1/3.
To check, we plug in our value for k into the original equation:

We found k to be 1/3, so for every instance of k, we plug in 1/3. To simplify, we combine the left side to get -1, and we combine the right side to get -1.
Since -1 = -1, our solution is correct.
The only way to do that is with +7 and -7 .