180 = 2x + 26
-26 -26
154 = 2x
÷2 ÷2
77 = x
One of the sides is 77
5+(-7)+3+(-6)=-5
Answer is zero
The chance of you selecting one randomly is 4/56, which simplifies to 1/14.
Notice that the box has a total os 4 + 5 + 3 = 12 balls, since there are 4 that are yellow, then, the probability to randomly obtaining a yellow ball in a single draw is:

therefore, the probability is 0.33 = 33%