If the equation 2x^2+bx+9=0 has only one real solution, then what is the value of b

Answer 1

to have one solution means the discriminant =0

b^2 -4ac =0

b^2 - 4(2)(9) = 0

b^2 = 72

b = sqr72= 3sq8 = 6sqr2 = about 6(1.414) = 8.484