What value(s) of b will cause 9x2 + bx + 4 = 0 to have one real solution?

15 and 14.7 are 1 apart, so 15 – 14.7 must be 1.

What is the length of the segment, endpoints of which are intersections of parabolas y=x^2− 11/4 x− 7/4 and y=− 7 /8 x^2+x+ 31/8 ?

F. a fair coin is thrown in the air four times. if the coin lands with the head up on the first three tosses, what is the probability that the coin will land with the head up on the fourth toss? a. 0 b. 1/16 c. 1/8 d. 1/2