What is the varible of
2x + 3 = 9

Each morning papa notes the birds feeding on his bird feeder. so far this month he has see. 59 blue jays, 68 black crows, 12 red robin's and 1 cardinal. what is the probability of a blue jay being the next bird papa sees

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?

Having a hard time understanding this question (see attachment).