Is the square root of 6 an irrational number

If there is no real number solution to the quadratic equation x^2+2x+c=0 what is a possible value of c? 1 -2 0 3

Which represents the solution set of the inequality 5x-9 < 21? a. x < 12/5 b. x > 12/5 c. x > 6 d. x < 6

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?