A
Given a quadratic in standard form : y = ax² + bx + c ( a ≠ 0 ), then
The x-coordinate of the vertex is
= - 
y = - 3x² + 2x - 7 is in standard form
with a = - 3, b = 2 and c = - 7, hence
= - 
= 
Substitute this value into the equation for y-coordinate
y = - 3 ()² + 2 ( ) - 7
= - + 
- 
= - 
vertex = ( , - ) → A
Answer:
Black = 84 cm^2
Blue = 84cm^2
gold = 60.2cm^2
1 ornament = 228.2 cm^2
100 ornaments - 22820 cm^2
Step-by-step explanation:
Black is a rectangle = A = l*w = 7*12 = 84 cm^2
We have 2 blue This is a triangle so multiply by 2 the area of a triangle
2 * A = 2(1/2 b*h) = bh = 12*7 = 84 cm^2
We have 2 gold This is a triangle so multiply by 2 the area of a triangle
2 * A = 2(1/2 b*h) = bh = 8.6*7 = 60.2 cm^2
The total surface area for one ornament is
84+84+60.2 = 228.2
100 ornaments
Multiply by 100
100 *228.2 = 22820 cm^2
There's no picture or anything about the shape in the question D: if you're able to explain in the comment I'll help you :D
Answer: c the third option
Step-by-step explanation:
The simple closed curve is called the base of the cone, and the fixed noncoplanar point is the vertex. ... Figure %: A right circular cone It is easy to see the close relationship between pyramids and cones. The only difference is the base--a pyramid is a cone with a polygonal base.
