Find the area of the shaded polygons

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

Arestaurant gives out a scratch-off card to every customer. the probability that a customer will win a prize from a scratch-off card is 25%. design and conduct a simulation using random numbers to find the experimental probability that a customer will need more than 3 cards in order to win a prize. justify the model for your simulation, and conduct at least 10 trials.

Don't know how to find x given these segment lengths