All categories

3 years ago

What is the value of 3-(-2)?

Mathematics

1 answer:

Fed [463]3 years ago

6 0

Answer:

Step-by-step explanation:

distribute the negative to ger 3(2), since a negative times a negative is positive. Then just multiply

You might be interested in

Suppose the roots of the polynomial $x^2 - mx + n$ are positive prime integers (not necessarily distinct). Given that $m < 20

Vsevolod [243]

Answer:

18 values for n are possible.

Step-by-step explanation:

Given the quadratic polynomial:

$x^2 - mx + n$

such that:

Roots are positive prime integers and

$m < 20$

To find:

How many possible values of $n$ are there ?

Solution:

First of all, let us have a look at the sum and product of a quadratic equation.

If the quadratic equation is:

$Ax^{2} +Bx+C$

and the roots are: $\alpha$ and $\beta$

Then sum of roots, $\alpha+\beta = -\frac{B}{A}$

Product of roots, $\alpha \beta = \frac{C}{A}$

Comparing the given equation with standard equation, we get:

A = 1, B = -m and C = n

Sum of roots, $\alpha+\beta = -\frac{-m}{1} = m$

Product of roots, $\alpha \beta = \frac{n}{1} = n$

We are given that $m$

$\alpha$ and $\beta$ are positive prime integers such that their sum is less than 20.

Let us have a look at some of the positive prime integers:

2, 3, 5, 7, 11, 13, 17, 23, 29, .....

Now, we have to choose two such prime integers from above list such that their sum is less than 20 and the roots can be repetitive as well.

So, possible combinations and possible value of $n (= \alpha \times \beta)$ are:

$1.\ 2, 2\Rightarrow n = 2\times 2 = 4\\2.\ 2, 3 \Rightarrow n = 6\\3.\ 2, 5 \Rightarrow n = 10\\4.\ 2, 7\Rightarrow n = 14\\5.\ 2, 11 \Rightarrow n = 22\\6.\ 2, 13 \Rightarrow n = 26\\7.\ 2, 17 \Rightarrow n = 34\\8.\ 3, 3\Rightarrow n = 3\times 3 = 9\\9.\ 3, 5 \Rightarrow n = 15\\10.\ 3, 7 \Rightarrow n = 21\\$

$11.\ 3, 11\Rightarrow n = 33\\12.\ 3, 13 \Rightarrow n = 39\\13.\ 5, 5 \Rightarrow n = 25\\14.\ 5, 7 \Rightarrow n = 35\\15.\ 5, 11 \Rightarrow n = 55\\16.\ 5, 13 \Rightarrow n = 65\\17.\ 7, 7 \Rightarrow n = 49\\18.\ 7, 11 \Rightarrow n = 77$

So,as shown above 18 values for n are possible.

3 0

3 years ago

What are the x-intercepts of the quadratic function? f(x) = x2-3x-10

zzz [600]

-2 and 5 (just put in a graphing calculator and find the zeros)

3 0

3 years ago

How do you solve the fraction 2 1/2 - 6

Slav-nsk [51]

You could easily change the 2 1/2 to a 2.5 and do 2.5-6=-3.5

8 0

3 years ago

The length of a rectangle is 3 meters greater than 2 times the width. The perimeter of the rectangle is 30 meters.What is the le

faust18 [17]

Answer:

11 meters

Step-by-step explanation:

Lets say that w = width of the rectangle, to start. If the length of the rectangle is 3 meters greater than 2 times the width, the length of the rectangle is equal to 3 + 2w.

The perimeter of the rectangle is 2 * length of rectangle + 2 * width of the rectangle. With the perimeter being equal to 30 and width being w and length being 2w+3:

The perimeter of the rectangle is 2(w) + 2(2w+3) = 30.

We first need to find out w first, which will give us the width of the rectangle. Taking it step by step, we get:

2w + 4w + 6 = 30

6w + 6= 30

6w = 24 which is done by subtracting both sides by 6 to put the variables on one side and the values on the other side

w = 4 which is done by dividing 6 on both sides

Ultimately, this gets width to be 4 meters. Now that we found the width, we need to plug w = 4 into the equation we set up for length which is 2w+3.

That being said, the ANSWER is:

length of rectangle = 2(4)+3 = 11 meters

Hope this helps! :)

4 0

3 years ago

In order for Aunt Lucy to save the desired $200,000 at age 65, how much will she need to save each month. Round your answer up t

balandron [24]

Answer:

$520.83

Step-by-step explanation:

7 0

3 years ago