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3 years ago

Abdullah expands (x - 3)2 and gets the answer x2 - 9. Describe what he has done wrong.

Mathematics

1 answer:

solniwko [45]3 years ago

4 0

Answer:

He squared the numbers inside without following the appropriate rule

Step-by-step explanation:

<u>what he should have done </u>

<u /> $(x-3)^2\\= x^2 - 2 *x*3+3^2\\= x^2-6x+9$

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Missing number in the series 9, ____, 6561, 43046721 is: 81 25 62 31 18 9. one number is 2 more than 3 times another. their sum

Nadusha1986 [10]

Alright, lets get started.

Missing number fom the series : 9, ..... , 6561, 43046721

43046721 is square of its previous number 6561, means

$6561^2 = 43046721$

It means the missing number will be square of its previous number

Means $9^2 = 81$ , so missing number is 81. : Answer

Next : one number is 2 more than 3 times another. their sum is 22. find the numbers.

Suppose one number is x and second number is y

As per given equation, $x = 3y + 2$ ......equation (1)

Their sum is 22 means, $x+y = 22$ .......equation (2)

Putting the value of x from equation1 into equation 2

$3y + 2 + y = 22$

$4y + 2 = 22$

Subtracting 2 in both sides

$4y + 2 - 2 = 22 - 2$

$4y = 20$

$y = 5$

$x = 22 - y = 22 - 5 = 17$

Means numbers are 17 and 5. : Answer

Next : the missing number in the series 1, 4, 27,____, 3125 is

1 could be written as 1

4 could be written as $2^2$

27 could be written as $3^3$

So , next number would be $4^4$

$4^4 = 256$

Next one is $5^5 = 3125$

So, the missing number is 256 : Answer

Next : the next number in the series 3, 4, 6, 7, 9, 10 is

After 3,4 (5) is mising, 6, 7 (8) is missing, 9, 10 (11) will be missing

So, next number will be 12. : Answer

Next : a farmer is planting a straight row of crops with 3 feet between each plant. if 23 are planted, what is the distance between the first and last plant?

Between 2 plants, the distance is = $3 * (2-1) = 3$

Between 3 plants, the distance is = $3 * (3-1) = 6$

So, between 23 plants, the distance is = $3 * (23-1) = 3 * 22 = 66$

hene the distance between first and last plant woule be 66 feet. : Answer

7 0

3 years ago

How long, in minutes, does it take to cover 24 miles at a rate of 12 miles per hour?

frutty [35]

It would take 120 minutes

4 0

3 years ago

Read 2 more answers

HELPPPP PLEASE<br>60 POINTS

soldi70 [24.7K]

Answer:

1056

Step-by-step explanation:

Find the area of each square and add them to find the area of the rectangle

The area of a square = side * side

The areas are:

1*1= 1

4*4 = 16

7*7 = 49

8*8 = 64

9*9 = 81

10*10 = 100

14*14 = 196

15*15 = 225

18*18 = 324

The sum of the areas =

324+225+196+100+81+64+49+16+1

= 1056 units ^2

3 0

3 years ago

Read 2 more answers

A wildlife photographer photographs a crocodile and then paddles against a river current for 6 km. Then, hoping to photograph a

Angelina_Jolie [31]

Answer:

5 or 6

Step-by-step explanation:

So I did it in a different way than shown in rsm classes. I said that the speed was x-2 and x.

then I said the distance was 6 and 15. If the time taken was 1 hour more, then we can come up with this equation:

Since the time is 6/x-2 or 15/x

15/x-6/x-2=1

multiply everything to get a common denominator then cancel it out to get

(15x-30)-6x=x^2-2x

11x-30=x^2

x^2-11x+30=0

(x-5)(x-6) is factored form.

so x=5 or x=6. this means that the speed of the boat is either 5km/h or 6 km/h

6 0

3 years ago

Janet researcher compares the math placement scores of college applicants who have, or have not taken a special college preparat

riadik2000 [5.3K]

Answer:

Step-by-step explanation:

Independent Variable (IV): Special college preparation program

How will you describe the IV: Independent variable or known as manipulated variable is a variable where the researcher purposely manipulate the variable to see how it affect the results of the experiment.

Dependent variables (DV): Math placement scores of college applicants

How will you measure the DV: DV can be measured by recording the math placement scores of each applicants who have or have not taken the special college preparation program.

Explanation: In this case, the researcher wants to see how taking special college preparation program (IV) can affect the math placement scores of the applicants (DV). Explanation: In this case, the researcher wants to see how taking special college preparation program (IV) can affect the math placement scores of the applicants (DV).

Hypothesis:

If the applicants take the special college preparation program, the applicants will have higher math placement scores compared to the one who have do not take the program.

8 0

3 years ago