Answer:
Step-by-step explanation:
<u>Quadratic Equation</u>
If the roots of a quadratic equation are known, we can form the equation as follows:
where x1 and x2 are the known roots, and a is the leading coefficient.
We are given the roots as x1=1 and x2=-6, and the leading coefficient as a=5, thus:
Operating:
Simplifying:
Multiplying:
2b/4=8 multiply both sides by 4
2b=32 divide both sides by 2
b=16
So Julia has 16 barrettes.
Volume of a cone =
The radius is 5ft, and the height is 16ft, therefore the answer is 418.88, which is option D***