1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Dmitry [639]
3 years ago
14

A N S W E R Q U I C K P L E A S E

Mathematics
1 answer:
chubhunter [2.5K]3 years ago
5 0

Answer:

1. A

2. D

3. D

Step-by-step explanation:

The standard form of a parabola is

y=\frac{1}{4p}(x-h)^2+k            ..... (1)

Where, (h,k) is vertex, (h,k+p) is focus and y=k-p is directrix.

1. The directrix of a parabola is y=−8 . The focus of the parabola is (−2,−6) .

k-p=-8                   ...(a)

(h,k+p)=(-2,-6)

k+p=-6            .... (b)

h=-2

On solving (a) and (b),  we get k=-7 and p=1.

Put h=-2, k=-7 and p=1 in equation (1).

y=\frac{1}{4(1)}(x-(-2))^2+(-7)

y=\frac{1}{4}(x+2)^2-7

Therefore option A is correct.

2 The directrix of a parabola is the line y=5 . The focus of the parabola is (2,1) .

k-p=5                   ...(c)

(h,k+p)=(2,1)

k+p=1            .... (d)

h=2

On solving (c) and (d),  we get k=3 and p=-2.

Put h=2, k=3 and p=-2 in equation (1).

y=\frac{1}{4(-2)}(x-(2))^2+(3)

y=-\frac{1}{8}(x-2)^2+3

Therefore option D is correct.

3. The focus of a parabola is (0,−2) . The directrix of the parabola is the line y=−3 .

k-p=-3                   ...(e)

(h,k+p)=(0,-2)

k+p=-2            .... (f)

h=0

On solving (e) and (f),  we get k=-2.5 and p=0.5.

Put h=0, k=-2.5 and p=0.5 in equation (1).

y=\frac{1}{4(0.5)}(x-(0))^2+(-2.5)

y=\frac{1}{2}(x)^2-2.5

y=\frac{1}{2}(x)^2-\frac{5}{2}

Therefore option D is correct.

You might be interested in
Which best describes the relationship between the successive terms in the sequence shown?
Alex Ar [27]

Given series is 2.4,-4.8,9.6,-19.2

To find whether it has common difference or common ratio let us find few differences and few ratios of consecutive terms.

Common difference of first 2 terms = 2nd term - first term = -4.8-2.4 = -7.2

Common difference of 2nd and 3rd terms = 3rd term - 2nd term = 9.6-(-4.8) = 14.4

Since those common differences are not equal the given series does not have common difference at all.

To check if it has common ratio or not let us find few ratios of consecutive terms.

Common ratio of first 2 terms = \frac{2nd term}{first term} = \frac{-4.8}{2.4} = -2

Common ratio of 2nd and 3rd terms = \frac{3rd term}{2nd term} = \frac{9.6}{-4.8} = -2.0

So, the given series has common ratio as -2.0

7 0
3 years ago
Read 2 more answers
I need help on 14 please
Fynjy0 [20]
2+x=50

That is what I would do. I hope this helps!
8 0
3 years ago
Read 2 more answers
Aaron tracks the time it takes him to mow lawns by writing coordinate points relating x, the time in hours it takes to mow a law
NARA [144]

Answer:

Slope of this line is given by:

<em>Aaron’s rate for mowing lawns is 0.5 acres per hour</em>

Step-by-step explanation:

It is given that time is tracked by Aaron related to x coordinate.

and the area of land mowed in acres is related to y coordinate.

Two of his points are given as:

(3, 1.5) and (5,2.5)

We know that the coordinates are represented in the form of (x,y)

i.e. first coordinate represents x coordinate and

second coordinate represents y coordinate.

So, it can be observed that:

x_1=3, y_1=1.5\\x_2=5, y_2=2.5

Change in x coordinate = x_2-x_1=5-3 = 2

i.e. total time taken is 2 hours.

Change in y coordinate = y_2-y_1=2.5-1.5 = 1

i.e. total land mowed taken is 1 acre.

In other words, <em>it takes 2 hours for Aaron to mow 1 acre of land.</em>

So, "option 1)  It takes Aaron about 1 hour to mow 2 acres." is incorrect.

<u>Rate of mowing</u> lawn is the <em>land mowed by Aaron in 1 hour</em>.

Land mowed in 2 hours = 1 acre

Land mowed in 1 hours = \frac{1}{2} acre i.e. 0.5 acre

Also, slope of a line is given as:

m = \dfrac{y_2-y_1}{x_2-x_1}

Here y_2 - y_1 = 1

x_2 - x_1 = 2

As per formula:

m = \dfrac{1}{2} = 0.5

So, option 2) Aaron’s rate for mowing lawns is 0.5 acres per hour.

6 0
3 years ago
Read 2 more answers
Hours worked versus salary.
taurus [48]

Answer:

whats the question

Step-by-step explanation:

8 0
3 years ago
A coin is flipped 40 times and it lands on head 16 timed based on the experimental probability how many heads would you protect
crimeas [40]
24 abcdefghijklmnopqrstuvwxyz


4 0
3 years ago
Other questions:
  • A 6 sided number cube is rolled 24 times and lands on 2 four times and on 6 three times.
    15·1 answer
  • Savanna had 404040 iris blooms last year. This year, she had 15\%15%15, percent more iris blooms. How many more iris blooms did
    9·1 answer
  • Can someone please help me with 3,4,5,6 pleaseeee!
    6·1 answer
  • 2y-x=3/4(-y+1) solve for y
    14·1 answer
  • I need help with this​
    11·2 answers
  • Lamont and Carmela both wrote an expression to show the area of the shaded region.
    5·1 answer
  • I am confused on this question.....please help!
    7·1 answer
  • To find slope, use the slope formula which is X2-Y2/X1-Y1<br> True<br> False
    6·2 answers
  • How do I do this number 5 and 6
    5·1 answer
  • What is the length of line segment s a? 1.89 ft 2.43 ft 3 ft 7 ft
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!