Help me please !!!!!!!

AlladinOne [14]

Answer:

$x = 3 \: \: \: \: \: \: or \: \: \: \: x = - \frac{3}{2}$

Step-by-step explanation:

$2x^2+3x-9=0 \\ 2x {}^{2} + 3x - 6x - 9 = 0 \\ x(2x + 3) - 3(2x + 3) = 0 \\ (x - 3) \: \: \: \: or \: \: \: \: \: (2x + 3) = 0 \\ x - 3 = 0 \: \: or \: \: \: 2x + 3 = 0 \\ x = 3 \: \: \: \: \: \: \: \: \: or \: \: \: \: x = - \frac { 3}{2}$

5 0

3 years ago

Sam has twice as many books as Jim. If Sam gives 12 books to Jim, they will have the same number of books. How many books do the

Neko [114]

Alright, lets get started.

Suppose number of books Jim have = x

Sam has twice as many books as Jim. So,

Number of books Sam have = 2x

If Sam gives 12 books to Jim, they will have the same number of books.

When Sam gives 12 books, his remaining books will be $= 2x - 12$

When Jim gets 12 books from Sam, his books will be $= x + 12$

And as per given question, they both now have equal books, so

$2x - 12 = x + 12$

Adding 12 in both sides

$2x - 12 + 12 = x + 12 + 12$

$2x = x + 24$

Subtracting x from both sides

$2x - x = x + 24 - x$

$x = 24$

It means Jim has number of books = 24

So, Sam has numberof books = $24 * 2 = 48$

So, they have number of books together = $24 + 48 = 72$ : Answer

Hope it will help :)

5 0

3 years ago

Read 2 more answers

PLEASE HELP !!!!!!!!!!

WITCHER [35]

Answer:

$x > 7$

Step-by-step explanation:

$7 + 2x > 42 - 3x \\ 2x + 3x> 42 - 7 \\ 5x > 35 \\ x > \frac{35}{5} \\ x > 7$

<h3>Hope it is helpful....</h3>

4 0

3 years ago

The regression equation, y = 8.5x + 30, is obtained after performing a regression analysis, where x represents the number of hou

dusya [7]

Answer: It is usefull.

Step-by-step explanation:

The regression squared talks to us about how well the model fits in the experimental data, where 0.0 means that the model does not fit at all, and 100% means that the model fits perfectly.

This is always true? well, really not, there are cases where you can have a regression square of 0.98, which would imply that the model is correct, but when you see the residual vs fit the plot, you may see some pattern, which implies that there is a problem with the model (you always expect to see randomness when you look at this graph). While for a prediction, this actually may work (at least in the range of the data points, outside this range the model and the data may not coincide at all)

Now, it still is useful in a certain range, so we can actually conclude that if R^2 = 0.949 represents a model that is useful for predicting the exam marks.

3 0

3 years ago

Find the area of the shaded region.

earnstyle [38]

There are four parts of a circle, so you have to find out the area of the circle:-

10 cm=Radius

$10^{2}$ =100

$\pi$ =3.14

3.14*100=314 $cm^{2}$

Now, find the area of the square box:-

Since half the side of the square is 10 cm, the total length of one side is 2*10 which is 20 cm.

Area=S*S

=20*20=400 $cm^{2}$

Now subtract the area of the box from the area of the square:-

400-314= 86 $cm^{2}$

That is the area of the shaded part.

Happy to help you!

8 0

3 years ago