Conic section (or simply conic) is a curve obtained as the intersection of the surface of a cone with a plane. The three types of conic section are the hyperbola, the parabola, and the ellipse. The circle is a special case of the ellipse, previously called the fourth type. Planes that pass through the vertex of the cone will intersect the cone in a point, a line or a pair of intersecting lines, called degenerate conics.
Answer:
15x2+10x-9x+7
8x3+20x2+3x+12
11x4+4x2-6x2-16
Step-by-step explanation:
Let's assume the number be x.
So, sum of a number and 10 can be written as x+10.
Now the given statement is "One half of the sum of a number and 10 ".
So, one half of x+10 can be written as 
The answer would be -9.72
Step-by-step explanation:

But we know that

and

so this leaves us with just
