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
slavikrds [6]
3 years ago
15

QUICK! A. –27 B. –3 C. 3 D. 27

Mathematics
1 answer:
Alex3 years ago
7 0

Answer:

C. 3

Step-by-step explanation:

-9 * -1/3

= -9/ -3

A negative divided by a negative is a positive

9/3

3

You might be interested in
A set of 3 consecutive integers has a sum of 27. which integers are they
Scilla [17]
They are 8, 9 and 10. 
5 0
3 years ago
A circle has the order pairs (-1, 2) (0, 1) (-2, -1) what is the equation . Show your work.
olga55 [171]
We know that:

(x-a)^2+(y-b)^2=r^2

is an equation of a circle.

When we substitute x and y (from the pairs we have), we'll get a system of equations:

\begin{cases}(-1-a)^2+(2-b)^2=r^2\\(0-a)^2+(1-b)^2=r^2\\(-2-a)^2+(-1-b)^2=r^2\end{cases}

and all we have to do is solve it for a, b and r.

There will be:

\begin{cases}(-1-a)^2+(2-b)^2=r^2\\(0-a)^2+(1-b)^2=r^2\\(-2-a)^2+(-1-b)^2=r^2\end{cases}\\\\\\
\begin{cases}1+2a+a^2+4-4b+b^2=r^2\\a^2+1-2b+b^2=r^2\\4+4a+a^2+1+2b+b^2=r^2\end{cases}\\\\\\
\begin{cases}a^2+b^2+2a-4b+5=r^2\\a^2+b^2-2b+1=r^2\\a^2+b^2+4a+2b+5=r^2\end{cases}\\\\\\


From equations (II) and (III) we have:

\begin{cases}a^2+b^2-2b+1=r^2\\a^2+b^2+4a+2b+5=r^2\end{cases}\\--------------(-)\\\\a^2+b^2-2b+1-a^2-b^2-4a-2b-5=r^2-r^2\\\\-4a-4b-4=0\qquad|:(-4)\\\\\boxed{-a-b-1=0}

and from (I) and (II):

\begin{cases}a^2+b^2+2a-4b+5=r^2\\a^2+b^2-2b+1=r^2\end{cases}\\--------------(-)\\\\a^2+b^2+2a-4b+5-a^2-b^2+2b-1=r^2-r^2\\\\2a-2b+4=0\qquad|:2\\\\\boxed{a-b+2=0}

Now we can easly calculate a and b:

\begin{cases}-a-b-1=0\\a-b+2=0\end{cases}\\--------(+)\\\\-a-b-1+a-b+2=0+0\\\\-2b+1=0\\\\-2b=-1\qquad|:(-2)\\\\\boxed{b=\frac{1}{2}}\\\\\\\\a-b+2=0\\\\\\a-\dfrac{1}{2}+2=0\\\\\\a+\dfrac{3}{2}=0\\\\\\\boxed{a=-\frac{3}{2}}

Finally we calculate r^2:

a^2+b^2-2b+1=r^2\\\\\\\left(-\dfrac{3}{2}\right)^2+\left(\dfrac{1}{2}\right)^2-2\cdot\dfrac{1}{2}+1=r^2\\\\\\\dfrac{9}{4}+\dfrac{1}{4}-1+1=r^2\\\\\\\dfrac{10}{4}=r^2\\\\\\\boxed{r^2=\frac{5}{2}}

And the equation of the circle is:

(x-a)^2+(y-b)^2=r^2\\\\\\\left(x-\left(-\dfrac{3}{2}\right)\right)^2+\left(y-\dfrac{1}{2}\right)^2=\dfrac{5}{2}\\\\\\\boxed{\left(x+\dfrac{3}{2}\right)^2+\left(y-\dfrac{1}{2}\right)^2=\dfrac{5}{2}}
7 0
3 years ago
6r + 7 = 13 + 7r what is r
kumpel [21]

Answer:

6r+7=13+7r

6r+7=7r+13

6r+7−7r=7r+13−7r

−r+7=13

−r+7−7=13−7

−r=6

\frac{-r}{-1} = \frac{6}{-1}

r=−6

Step-by-step explanation:

:) This is the answer

6 0
3 years ago
Read 2 more answers
John got 24 out of 25 total questions correct on his test. What percent did he score on his test?
mamaluj [8]

Answer:

24 out of 25 is equal to 96%

96% = A

Step-by-step explanation:

7 0
3 years ago
Read 2 more answers
What is the length of AC?<br> ОЗft<br> o4ft<br> 9 ft<br> 09 ft<br> o18 ft
Nezavi [6.7K]

Answer:

18 ft

Step-by-step explanation:

4 0
3 years ago
Read 2 more answers
Other questions:
  • The angles of a triangle are 80º, 2x + 2º, and 5xº. What is the value of x?
    11·1 answer
  • Henry grabs one shoe at a time at random without replacement from a box of ten shoes in his closet. The box contains 4 brown sho
    11·1 answer
  • I need to convert this to a scientific notation 286,300,000,000.00
    14·1 answer
  • What is the approximate value of x in the equation below. log3/4 25=3x-1
    14·2 answers
  • Determine whether or not F is a conservative vector field. If it is, find a function f such that F = ∇f. (If the vector field is
    13·1 answer
  • Mantago want to borrow 10,000 to buy a car. He examined his budget and decides that he can afford a payment of $200 a month
    10·1 answer
  • Use multiplication to find 2 equivalent fraction for 3/4 and 4/5
    9·1 answer
  • Write the fraction equivalent of each decimal 36.90
    14·1 answer
  • Question 5 (2 points)<br> Given the function rule y = 3x + 11, what is the value of y if x = 27
    7·2 answers
  • Find the median for this list of data. 85,84,82,88,64,90,85,78​
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!