All categories

3 years ago

Which problem could be solved by evaluating the expression 7 x (-3)?

Mathematics

2 answers:

Tasya [4]3 years ago

6 0

Answer:

The answer is -21

Step-by-step explanation:

To find the answer just multiply 7 by 3 and that's 21, so just add a negative sign to 21 and you get -21. I hope this helps :) please give me brainliest :)

NNADVOKAT [17]3 years ago

5 0

Answer:

C: A cold front comes in and causes the temperature to drop 3 degrees every hour. What is the change in temperature after 7 hours?

You might be interested in

vanessa invested $2,500 into an account that will increase in value by 3.5% each year. Write an exponential function to model th

astraxan [27]

Answer: (i) A = 2500 ( $(1.035)^{n}$

(ii) A =$ 4,974.47

Step-by-step explanation:'

The exponential function is given as :

A = P $(1+r)^{n}$

Where :

A = amount

P = principal

r = rate %

n = number of years

substituting , the exponential function to model the situation becomes

A = 2500 ( $(1.035)^{n}$

(ii) when n = 20 , the Amount becomes

A = 2500( $(1.035)^{20}$

A =$ 4,974.47

4 0

3 years ago

A cookie recipe states for every three cups of flour,1 teaspoon of vanilla are needed. how many teaspoons are needed for five cu

Brrunno [24]

For 3 cups... vanilla needed - 1 teaspoon
for 1 cup...vanilla needed- 1/3 teaspoon
for 5 cups, vanilla needed- 5/3 teaspoon

In short , 1.67 or 5/3 teaspoon of vanilla is needed for 5 cups of floor

3 0

3 years ago

Solve & Justify: 3(5x + 2) = 2(3x - 6)

Zanzabum

Answer:

-2

Step-by-step explanation:

15x+6=6x-12

15x-6x=-12-6

9x=-18

x=-2

7 0

3 years ago

Find out the number of combinations and the number of permutations for 8 objects taken 6 at a time. Express your answer in exact

umka2103 [35]

Solution:

The permutation formula is expressed as

$\begin{gathered} P^n_r=\frac{n!}{(n-r)!} \\ \end{gathered}$

The combination formula is expressed as

$\begin{gathered} C^n_r=\frac{n!}{(n-r)!r!} \\ \\ \end{gathered}$

where

$\begin{gathered} n\Rightarrow total\text{ number of objects} \\ r\Rightarrow number\text{ of object selected} \end{gathered}$

Given that 6 objects are taken at a time from 8, this implies that

$\begin{gathered} n=8 \\ r=6 \end{gathered}$

Thus,

Number of permuations:

$\begin{gathered} P^8_6=\frac{8!}{(8-6)!} \\ =\frac{8!}{2!}=\frac{8\times7\times6\times5\times4\times3\times2!}{2!} \\ 2!\text{ cancel out, thus we have} \\ \begin{equation*} 8\times7\times6\times5\times4\times3 \end{equation*} \\ \Rightarrow P_6^8=20160 \end{gathered}$

Number of combinations:

$\begin{gathered} C^8_6=\frac{8!}{(8-6)!6!} \\ =\frac{8!}{2!\times6!}=\frac{8\times7\times6!}{6!\times2\times1} \\ 6!\text{ cancel out, thus we have} \\ \frac{8\times7}{2} \\ \Rightarrow C_6^8=28 \end{gathered}$

Hence, there are 28 combinations and 20160 permutations.

7 0

1 year ago

Un móvil azul de 573 g se encuentra en movimiento sobre un carril metálico. Si sobre el móvil, el resorte ejerce una fuerza haci

ad-work [718]

Answer:

The total mechanical energy is 0.712 J.

Step-by-step explanation:

A blue 573 g mobile is moving on a metal rail. If on the mobile, the spring exerts a force to the right of modulus 0.85 N and in the indicated position the kinetic energy of the mobile-spring system is 0.47 J and its elastic potential energy is 0.242 J. Determine the mechanical energy of the system mobile-spring in the position shown as indicated in the figure.

The total mechanical energy is given by the sum of the kinetic energy and the potential energy.

Kinetic energy = 0.47 J

Potential energy = 0.242 J

The total mechanical energy is

T = 0.47 + 0.242 = 0.712 J

4 0

3 years ago

Which problem could be solved by evaluating the expression 7 x (-3)?​

Which problem could be solved by evaluating the expression 7 x (-3)?