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3 years ago

What are the coordinates of the point obtained if the point A=(3,7) is rotated 180 degrees about the origin?

Mathematics

1 answer:

Yuliya22 [10]3 years ago

8 0

Answer:

B. (-3, -7)

Step-by-step explanation:

Anytime you rotate a number 180° about the origin, the numbers in the coordinates become their opposites.

-3 is the opposite of 3 and -7 is the opposite of 7.

Therefore, your new coordinates are (-3, -7)

(x,y) becomes (-x,-y)

You might be interested in

Tyrone runs 5 mph how far can he travel in two hours and 30 minutes

zaharov [31]

Answer:

12.5 miles

Step-by-step explanation:

5x2.5=12.5 miles

5 0

3 years ago

All of these ODEs model a system with a spring, mass and dashpot.

Wewaii [24]

Answer:

− 3 y ' ' − 3 y ' + 3 y = 0 : over-damped

− 2 y ' ' − 4 y ' + 1 y = 0 : over-damped

1 y ' ' + 7 y ' + 5 y = 0: over-damped

Step-by-step explanation:

Using the characteristic equation you can express a differential equation of order n as an algebraic equation of degree n:

$a_ny^n+a_n_-_1y^{n-1}+...+a_1y'+a_oy=0$

This differential equation will have a characteristic equation of the form:

$a_nr^n+a_n_-_1r^{n-1}+...+a_1r+a_o=0$

Now, you can classify the solution for a differential equation using a simple method. In order to do it, you just need to use the discriminant.

If the discriminant is greater than zero, the solution is over-damped

If the discriminant is less than zero, the solution is under-damped

If the discriminant is equal to zero, the solution is critically damped

So, given the differential equation:

$-3y''-3y+3y=0$

Which has characteristic equation of the form:

$-3r^2-3r+3=0$

The quadratic polynomial of the form:

$ar^2+br+c=0$

Has discriminant:

$Disc=b^2-4ac$

In this case:

$a=-3\\b=-3\\c=3$

So:

$Disc=(-3)^2-4(-3)(3)=9-(-36)=45$

In this case:

$Disc=45>0$

Therefore the solution is over-damped.

Now, given the differential equation:

$-2y''-4y'+1y=0$

Which has characteristic equation of the form:

$-2r^2-4r+1=0$

The quadratic polynomial of the form:

$ar^2+br+c=0$

Has discriminant:

$Disc=b^2-4ac$

In this case:

$a=-2\\b=-4\\c=1$

So:

$Disc=(-4)^2-4(-2)(1)=16+8=24$

In this case:

$Disc=24>0$

Therefore the solution is over-damped.

Finally, given the differential equation:

$1y''+7y'+5y=0$

Which has characteristic equation of the form:

$1r^2+7r+5=0$

The quadratic polynomial of the form:

$ar^2+br+c=0$

Has discriminant:

$Disc=b^2-4ac$

In this case:

$a=1\\b=7\\c=5$

So:

$Disc=(7)^2-4(1)(5)=49-20=29$

In this case:

$Disc=29>0$

Therefore the solution is over-damped.

6 0

3 years ago

How many integers between 100 and 999 (inclusive) have distinct digits

daser333 [38]

Answer:

648

Step-by-step explanation:

Running this in Python, with the code as follows,

import math

cur_numbers = [0] * 3

num = 0

for i in range(100, 1000):

cur_numbers[2] = i % 10

i = math.floor(i/10)

cur_numbers[1] = i % 10

i = math.floor(i/10)

cur_numbers[0] = i % 10

if(len(set(cur_numbers)) == 3):

num += 1

print(cur_numbers)

print(num), we get 648 as our answer.

Another way to solve this is as follows:

There are 9 possibilities for the hundreds digit (1-9). Then, there are 10 possibilities for the tens digit, but we subtract 1 because it can't be the 1 same digit as the hundreds digit. For the ones digit, there are 10 possibilities, but we subtract 1 because it can't be the same as the hundreds digit and another 1 because it can't be the same as the tens digit. Multiplying these out, we have

9 possibilities for the hundreds digit x 9 possibilities for the tens digit x 8 possibilities for the ones digit = 648

5 0

2 years ago

Which is the approximate solution to the system y = 0.5x + 3.5 and y = −A system of equations. y equals 0.5 x plus 3.5. y equals

Elena L [17]

Answer:

The approximate solution of the system of equations is the point (-2.7,2.1)

Step-by-step explanation:

we have

$y=0.5x+3.5$ -----> equation A