All categories

3 years ago

Simplify:4(r + 1) + 3r A. 4r + 4 B. 5r + 1 C. 7r + 1 D. 7r + 4

Mathematics

2 answers:

klasskru [66]3 years ago

6 0

Answer:

look in the explanation, it is in there

Step-by-step explanation:

i don't know if you are distributing or just using PEMDAS .

if you are distributing then: do in the equation 4(r + 1) + 3r.. do 4 x r and 4 x 1 , now you have 4r + 4 + 3r

7r +4

is what i got!

If you are doing PEMDAS then: first you do what is inside the perenthisis ()

4(r + 1) +3r changes into

4( r1 ) + 3r now you do multipulcation because that in the "M" in pemdas

4r + 3r, then if you are using like terms you would add them

i hope this helps you out!

scoray [572]3 years ago

5 0

The correct answer is , D. 7r + 4
using the pemdas method will result in the correct answer .

1. distribute 4 to r and 1
•4r and 4 (4r + 4)
2. combine like terms
•4r and 3r (4r+3r)
3. add like terms together
•4r + 3r = 7r
4. since our constant from step one has no other like terms , it stays as is resulting in our answer being : D. 7r + 4

You might be interested in

A survey of 32 different gas stations in Texas found the average price of gasoline to be $3.19 a gallon with a sample standard d

Leni [432]

Answer:

The value of test statistic is -4.1247

Step-by-step explanation:

We are given the following in the question:

Population mean, μ = $3.26 a gallon

Sample mean, $\bar{x}$ = $3.19 a gallon

Sample size, n = 32

Sample standard deviation, σ = $0.096

First, we design the null and the alternate hypothesis

$H_{0}: \mu = 3.26\text{ dollars a gallon}\\H_A: \mu < 3.26\text{ dollars a gallon}$

We use one-tailed t test to perform this hypothesis.

Formula:

$t_{stat} = \displaystyle\frac{\bar{x} - \mu}{\frac{\sigma}{\sqrt{n}} }$

Putting all the values, we have

$t_{stat} = \displaystyle\frac{3.19 - 3.26}{\frac{0.096}{\sqrt{32}} } = -4.1247$

Thus, the value of test statistic is -4.1247

3 0

2 years ago

Consider a binomial distribution of 200 trials with expected value 80 and standard deviation of about 6.9. Use the criterion tha

mote1985 [20]

Answer:

The correct answer is option 'a' : 120 is more than 2.5 standard deviations above the expected value.

Step-by-step explanation:

For an exponential distribution we have

The expected value μ = 80

No of trails n = 200

Thus we have

$p=\frac{80}{200}=0.4$

The deviation is related to expected value and probability as

$\sigma =\sqrt{np(1-p)}\\\\\therefore \sigma =\sqrt{200\cdot 0.4\cdot (1-0.4)}=6.9$

Thus the values between the given deviation is

$x_{1}=80-2.5\times 6.9=62.75\\\\x_{2}=80+6.9\times 2.5=97.25$

Now since 120 successes are out of the range of [62.75,97.25] thus 120 is more than the expected value.

5 0

3 years ago

You are given the equation 27bx7•cx8•7xd=455x27. If b and c are both integers greater than 1 and b less than cb

jolli1 [7]

Answer:

The question is not so clear and complete

Step-by-step explanation:

But for questions like this, since the equation has been given, what is expected is for us to make comparison, compare the RHS with the LHS or by method of comparing coefficients.

We follow the stated conditions since we are told that b and c are both integers which are greater than 1 and b is less than the product of cb. from these conditions, we can compare and get the values of b , c and d.

Another approach is to assume values, make assumptions with the stated conditions, however, our assumptions must be valid and correct if we substitute the assumed values of b, c and d in the equation, it must arrive at the same answer for the RHS. i.e LHS = RHS

5 0

2 years ago

Write the coordinate rule to describe The translasion

sergejj [24]

Answer:

The coordinates are:

A ( 4,7 )

B ( 8,10 )

c ( 7,7 )

Step-by-step explanation:

You could take the original coordinates and add the x value with 3 and y value with 6. Like for example...

The original coordinates of C is ( 4,1 ). Hence you could add the x value with 3 and y value with 6. 4 + 3 and 1 + 6 giving you the coordinates after translation = ( 7,7 )

6 0

2 years ago

Solve using substitution.<br> y = -10x-10<br> y = -3x + 4

Nikolay [14]

-10x-10 = -3x+4
+3x +3x
————————
-7x-10 = 4
+10 +10
————————
-7x = 14
then divide -7 on both side of the equal sign
you’ll get x=-2

then plug in -2 as x into one of the equations ( it doesn’t matter which one)

y= -10(-2)-10 = 20-10= 10

so y=10

4 0

3 years ago