hectictar

5^3 = 5 * 5 * 5 = 125      

To multiply this out..

4(x + 4)(x - 1)

First we can multiply the 4 by (x + 4)

= (4x + 16)(x - 1)

Next, let's multiply the (4x + 16) by (x - 1) ...to do this, we need to multiply each thing in the first set of parenthesees by each thing in the second set of parenthesees and add the products together.

= (4x)(x) + (4x)(-1) + (16)(x) + (16)(-1)

= 4x² - 4x + 16x - 16

= 4x² + 12x - 16

How many soccer balls come in a box?

\(\sqrt{850}=5\sqrt{34}\approx 29.1547594742265024\)

So no....850 is not a perfect square

Here, CD is the height of the building.

tan 36º = CD / BC

BC tan 36º = CD

BC = CD / tan 36º

tan 20º = CD / (600 + BC)

(600 + BC) tan 20º = CD

BC = CD/tan 20º - 600

\(\frac{CD}{\tan36}=\frac{CD}{\tan20}-600 \\~\\ \frac{CD}{\tan36}-\frac{CD}{\tan20}=-600 \\~\\ CD(\frac1{\tan36}-\frac1{\tan20})=-600 \\~\\ CD=-600\div(\frac1{\tan36}-\frac1{\tan20}) \\~\\ CD \approx 437.606 \text{ meters}\)

For this we can use the elimination method.

5x + 2y = -2

3x – 5y = 17.4

Multiply the top equation through by \(\frac52\) .

\(\frac{25}{2} \) – 5y = -2

Now line this up with the second equation and add straight down.

    \(\frac{25}{2} \)x    +    5y = -5

+   3x      –    5y = 17.4

     15.5x +    0y = 12.4

15.5x = 12.4

x = 12.4/15.5

x = 0.8

Now just use this value for x in either equation to find y.

5(0.8) + 2y = -2

4 + 2y = -2

2y = -6

y = -3

9x² - 6x

I don't really know what the instructions say to do...but we can factor out a 3x like this:

= 3x(3x - 2)

Can you give an example of one of these problems?

The most we can do here is simplify, since there is no equal sign in the original problem.

   9^2 - 6x

= 81 - 6x

And, if you want, we can factor out a 3.

= 3(27 - 2x)