I need help plz someone help me solved this problem I need help ASAP! I will mark you as brainiest!

 k = -9

Step-by-step explanation:

kx² - 12x - 4 = 0

In order to have exactly one solution, it must be a perfect square.

Assume k is negative and factor out a negative 1.

-1(kx² + 12x + 4) = 0

The middle term = 12x

                               12x = 4x√k

                                3   = √k

                                9 = k

-1(9x² + 12x + 4) = 0

-9x² - 12x - 4 = 0

k=-9

it will be a cylinder. with a diameter of 8 and 4 single pieces high

step-by-step explanation:

14

step-by-step explanation:

14 x 3 = 42