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3 years ago

Evaluate 5x 2+ 2(4x – 7) – 8x for x = 3.

Mathematics

1 answer:

Sauron [17]3 years ago

6 0

Answer:

10x-14

Step-by-step explanation:

You might be interested in

Find the product (7m^2-3m-7)(m^2-7m-6)

earnstyle [38]

Answer:

7m^4-52m^3-28m^2+67m+42

Step-by-step explanation:

(7m^2-3m-7)(m^2-7m-6)

7m^4-3m^3-7m^2-49m^3+21m^2+49m-42m^2+18m+42

7m^4-3m^3-49m^3-7m^2+21m^2-42m^2+49m+18m+42

7m^4-52m^3-28m^2+67m+42

4 0

3 years ago

If n is a positive integer, how many 5-tuples of integers from 1 through n can be formed in which the elements of the 5-tuple ar

erma4kov [3.2K]

Answer:

$\frac{(n+4)*(n+3)*(n+2)*(n+1)*n}{120}$

Step-by-step explanation:

Given

5 tuples implies that:

$n = 5$

$(h,i,j,k,m)$ implies that:

$r = 5$

Required

How many 5-tuples of integers $(h, i, j, k,m)$ are there such that $n\ge h\ge i\ge j\ge k\ge m\ge 1$

From the question, the order of the integers h, i, j, k and m does not matter. This implies that, we make use of combination to solve this problem.

Also considering that repetition is allowed: This implies that, a number can be repeated in more than 1 location

So, there are n + 4 items to make selection from

The selection becomes:

$^{n}C_r => ^{n + 4}C_5$

$^{n + 4}C_5 = \frac{(n+4)!}{(n+4-5)!5!}$

$^{n + 4}C_5 = \frac{(n+4)!}{(n-1)!5!}$

Expand the numerator

$^{n + 4}C_5 = \frac{(n+4)!(n+3)*(n+2)*(n+1)*n*(n-1)!}{(n-1)!5!}$

$^{n + 4}C_5 = \frac{(n+4)*(n+3)*(n+2)*(n+1)*n}{5!}$

$^{n + 4}C_5 = \frac{(n+4)*(n+3)*(n+2)*(n+1)*n}{5*4*3*2*1}$

$^{n + 4}C_5 = \frac{(n+4)*(n+3)*(n+2)*(n+1)*n}{120}$

<u><em>Solved</em></u>

6 0

3 years ago

The grounds keeper of Estofer Park has to mow 14,623 sq. ft. of grass. He can mow 13 sq. ft of grass in one minute. How many min

MA_775_DIABLO [31]

Answer: $1,124\frac{11}{13}\ minutes$

Step-by-step explanation:

Let be "x" the time in minutes that will take him to mow the entire park.

You know that he can mow 13 square feet in 1 minute and he has to mow 14,623 square feet.

Then, you can write the following proportion:

$\frac{1}{13}=\frac{x}{14,623}$

Solving for "x", you get:

$x=\frac{14,623}{13}\ min$

To write that improper fraction as a mixed number:

- The quotient when you divide the numerator by the denominator of the fraction obtained, is $1,124$ (This will be the whole number).

- The remainder of that division is $11$ (This will be the numerator of the fraction).

- The denominator does not change.

Then:

$x=1,124\frac{11}{13}\ min$

8 0

3 years ago

Need help with this question click to see

blondinia [14]

Answer:

1) u > 4

2) 7 < u

3) u < 4

4) 7 > u

Step-by-step explanation:

1) subtract 6 - 2

2) add 3 + 4

3) subtract 4 on both sides (8-4)

4) subtract 9 - 2

7 0

3 years ago

How do you find the x-intercepts if given the following polynomial in factored form?

elena-14-01-66 [18.8K]

Answer:

Step-by-step explanation:

You know the intercepts occur at x = 0, so set each part of the factored form equal to zero and solve for x.

The first part, plain X = 0, so X = 0 is a root, an x-intercept

The second part (X-2)^2 = 0, so X = 2 is another root. Since the function is being squared, this root will happen twice. The function crosses this root twice.

The third part (x+4) = 0, so x = -4 is another root.

Finally, (x+1) so x = -1 is another root.

So you have X = 0, X = 2, X = -4, X = -1 as your x-intercepts

3 0

3 years ago