Answer:
vertex at (1, -3)
Step-by-step explanation:
When x = 0
y² + 6y + 1 = 0
y² + 6y + = -1
y² + 6y + 9 = -1 + 9
(y + 3)² = 8 or (-y - 3)² = 8
y + 3 = √8 or -y - 3 = √8
y = - 3 +√8 or y = -3 - √8
(0, - 3 +√8) and (0, -3 - √8)
The mid point between these two is the average
y = ( - 3 + √8 + -3 - √8) / 2 = - 3
y² + 6y + 8x + 1 = 0
(-3)² + 6(-3) + 8x + 1 = 0
9 - 18 + 1 = -8x
- 8 = -8x
x = 1
No solution
The answer is D
223
-119
104
In stead of doing 3-9 and 2-1 do 23-19 then 2-1
It costs $3.63 more for the gold die than the gold plated die.
The volume of each half of the die is given by the formula
V=1/3s³.
This means the total volume is V = 2(1/3s³) = 2(1/3(2³)) = 16/3 = 5.33 mm³.
For the solid gold die, we know that it weighs 0.02g per mm³:
5.33(0.02) = 0.1066g
Gold costs $40.38 per gram:
40.38(0.1066) = $4.30
For the plastic die, plastic weighs 0.01 g per mm³:
0.01(5.33) = 0.0533g
Plastic costs $10 per gram:
0.0533(10) = 0.533 ≈ $0.54.
We also need to find the surface area, as it will be painted. Each face is an equilateral triangle; the area of a triangle is given by the formula
A = 1/2bh
We need to use the Pythagorean theorem to find the height. The height will be one leg and 1/2 of the base will be the other; the slanted side will be the hypotenuse:
h² + (1/2(2))² = 2²
h² + 1² = 2²
h² + 1 = 4
h² = 3
h = √3
The area of the triangle would then be A = 1/2bh = 1/2(2)(√3) = √3. There are 8 such faces on the die, so the total surface area would be 8√3 = 13.86mm².
Paint costs $0.01 per mm²:
13.86(0.01) = 0.1386 ≈ $0.14
Together the cost for the plastic is 0.14+0.53 = $0.67.
The difference between it and the cost for the gold die is 4.30 - 0.67 = $3.63.
Y = 2x + 0.5
or
y = 2x + 1/2