Solve the equation with the quadratic formula 4k^2-11k-18=0

Answer:
D
Step-by-step explanation:
Quadratic formula tells us that the roots are equal to:
[tex]\frac{-b\pm \:\sqrt{b^2-4ac}}{2a}[/tex]
The letters are just the coefficients, so a = 4, b = -11, and c = -18. Plugging these values into the formula we get:
[tex]\frac{-11\pm \sqrt{11^2-4\cdot \:4\left(-18\right)}}{2\cdot \:4}[/tex]
Which when simplified tells us that the roots are:
[tex]\frac{-11+\sqrt{409}}{8}[/tex] or [tex]\frac{-11-\sqrt{409}}{8}[/tex]
Remember the plus or minus sign is what gives us two answers.