Answer:

Step-by-step explanation:
we know that
The surface area of the cone is given by the formula

where
r is the radius of the base
l is the slant height
we have

substitute


Answer:
Scalene triangle
Step-by-step explanation:
scalene triangle is a triangle where the lengths of all three sides are different, it comprises of both obtuse and acute angles,all giving a sum of 180 degrees
f(x) = -5x^2 - x + 20;
f(3) = -5*3^2 - 3 + 20 = -5*9 - 3 + 20 = -45 - 3 + 20 = -28;