The general form of a parabola when using the focus and directrix is:
(x - h)² = 4p(y - k) where (h, k) is the vertex of the parabola and 'p' is distance between vertex and the focus. We use this form due to the fact we can see the parabola will open up based on the directrix being below the focus. Remember that the parabola will hug the focus and run away from the directrix. The formula would be slightly different if the parabola was opening either left or right.
Given a focus of (-2,4) and a directrix of y = 0, we can assume the vertex of the parabola is exactly half way in between the focus and the directrix. The focus and vertex with be stacked one above the other, therefore the vertex will be (-2, 2) and the value of 'p' will be 2. We can now write the equation of the parabola:
(x + 2)² = 4(2)(y - 2)
(x + 2)² = 8(y - 2) Now you can solve this equation for y if you prefer solving for 'y' in terms of 'x'
Answer: 7.2$
hope it helps :)
step-by-step explanation:
Cost of each box = 3$
Cost of 3 boxes without 20% coupon = 9$
With 20% off Coupon = 9 by 100 multiplied by 20
(the zero's cut with each other leaving)
= 9 by 10 multiplied by 2
(9 multiplied by 2 = 18)
= 18 by 10
(18 divided by 10 = 1.8)
= the 20% of 9$ is equal to 1.8
when subtracted with the total cost leaves 7.2$
Answer:
Pi: Irrational
2/9: Rational
225: Rational
0.167: Irrational <--- fourth one
Step-by-step explanation:
Not sure about the 4th one, but the others are good :)
Answer:
17
Step-by-step explanation:
2 (4) + 6^2 / 4 = 8 + 36 / 4 = 8 + 9 = 17.
When solving these types of problems, make sure to use BEDMAS. For example, in this question, do x^2 / 4 before 2y + (x^2 / 4).
Answer:
c. 2144
Step-by-step explanation:
i searched it up