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HERE

Thank you Quazars,  

X is an angle so you have to use inverse trig.

x=tan^-1(opp/adj)=tan^-1(15/7)

Inverse tan is the same as arc tan so on the web2 calculator it is

atan(15/7)

$$\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}^{\!\!\mathtt{-1}}{\left({\frac{{\mathtt{15}}}{{\mathtt{7}}}}\right)} = {\mathtt{64.983\: \!106\: \!521\: \!9^{\circ}}}$$

I just want to think this through more than Alan needed to.     

$$Volume\;of\:sphere=\frac{4}{3}\pi r^3$$         $$Need\; to \;find\; r\;\;cm$$ 

$$Density=\dfrac{19.5g}{cm^3}$$     

  $$If\; there \;is \;\dfrac{19.5g}{cm^3} \qquad Then\; it \;would\; also\; be\; true \;to\; say \;that\; there\; are \; \dfrac{cm^3}{19.5g}$$

$$mass=60kg=60000g$$

so

$$\dfrac{cm^3}{19.5g}\times 60000g=3076.923cm^3 \qquad \mbox{The grams cancel out}$$

$$\begin{array}{rll}
3076.923&=&\frac{4}{3}\pi r^3\\\\
3076.923*3/(4\pi) &=& r^3\\\\
r&=&\sqrt[3]{3076.923*3/(4\pi) }\\\\
r&=&9.023cm
\end{array}$$

$${\left({\frac{{\mathtt{3\,076.923}}{\mathtt{\,\times\,}}{\mathtt{3}}}{\left({\mathtt{4}}{\mathtt{\,\times\,}}{\mathtt{\pi}}\right)}}\right)}^{\left({\frac{{\mathtt{1}}}{{\mathtt{3}}}}\right)} = {\mathtt{9.022\: \!827\: \!882\: \!792\: \!352}}$$

(1+r)=(1+0.17/12)^12

$${\left({\mathtt{1}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{0.17}}}{{\mathtt{12}}}}\right)}^{{\mathtt{12}}}{\mathtt{\,-\,}}{\mathtt{1}} = {\mathtt{0.183\: \!891\: \!728\: \!240\: \!085\: \!4}}$$

Effective rate is 18.39% per annum (correct to 2 dp)

I was not referring to Rosala's outer beauty although i am sure she is very pretty.

I was referring to her inner beauty!   

Rosala has a beautiful personality.

I also really liked your poem Rosala!

Another excellent explanation pokemonfan58.  

Have you googled it yet?

That is always a good place to start.

I haven't actually heard of it.

if r and s are the roots of 2x^2 -5x -7 =0 what is the value of r/s + s/r ?

$$ax^2+bx+c=0 \\
\mbox{The roots are: } x_{1,2}= {-b\pm\sqrt{b^2-4ac}\over2a}\\
\mbox{or } x_{1,2}= {-b\pm\sqrt{D}\over2a} \quad \mbox{ set }\quad D=b^2-4ac\\
\mbox{So we have: } r=x_1={-b+\sqrt{D}\over 2a}\\
\mbox{and } s=x_2={-b-\sqrt{D}\over 2a}$$

$$\\ \boxed{{r\over s}+{s\over r} =} {-b+\sqrt{D}\over -b-\sqrt{D}}+{-b-\sqrt{D}\over -b+\sqrt{D}}\\ \\
={(-b+\sqrt{D})^2 +(-b-\sqrt{D})^2\over (-b-\sqrt{D})(-b+\sqrt{D})}\\\\
={2(-b)^2+2(\sqrt{D})^2 \over (-b)^2-(\sqrt{D})^2}\\\\
={2b^2+2D \over b^2-D} \quad | \quad D= b^2-4ac$$

$$\\={2b^2+2b^2-8ac \over b^2-b^2+4ac} \\\\
={4b^2-8ac \over 4ac} \\\\
={b^2 \over ac} - 2 \quad | \quad a=2 \quad b=-5 \quad c=-7$$

$$\\={ (-5)^2 \over 2*(-7) } -2 \\\\
={ 25 \over (-14) } -2 \\\\
={ -25-2*14 \over 14 } \\\\
={ -\frac{53} {14} } \\\\
={ -\frac{14*3+11} {14} } \\\\
={ -3-\frac{11} {14} } \\\\
\boxed{={ -3\frac{11} {14} }}$$

Ninja has answered correctly but I think that perhaps you mean 

0.15²*100

I went to the format drop down menu and choose superscript to write this but this is an easider way,

0.15^2*100    The hat means 'to the power of'

Now if this is what you meant you can go straight to the site calc on the home page to get an answer. OR

15squared=225

so 0.15*0.15=0.0225

0.0225*100=2.25

No one has answered you because we do not understand what you are asking  

I assume you mean this:   log₆ 45

A log is an exponent...in this case it's the exponent (power) - call it "x" - that we put on 6 to raise it to 45. We can evaluate this by something called the "change of base" rule, Specifically:

x = log 45 / log6   ≈ 2.1245387872348441

Verify for yourself that 6^{2.1245387872348441} ≈ 45

I'm sorry, I did a number line before I opened the question so I didn't realise that you had already done one Ninja.

I can't bear to let mine go to wast so here it is.

On number lines the bigger number is always on the right.

Like 2 is bigger than 1

So here you can see that -0.8 is bigger than -1.4

----------------------

I'll have to take a look at what Ninja used for his numberline.  I agree it is a good one!  Thanks for the info and thumbs up from me.  

Maybe you could add it, with a covering blurb, to your information pages etc thread

I did mine with GeoGebra.

-----------------------

This is not a question.  It is a statement.  If you graphed it it would be a line.

The y intercept would be 4 and the gradient is -1/2

Maybe there was more to this questions?   

    What a great effort pokemonfan58!

I rarely double up on CPhill's points.  I only do that for extra special answers.

I am doing it here for you.  Good work!        

                                                ♬ ♬ MELODY ♬ ♬

I assume that by x you mean the angle of x. You can use the trigonometric function tan to find the angle.

atan(15/7) which is equal to approximately 65 degrees. ( Rounded to nearest whole number)

Deleted Deleted

Multiply everything through by 100 to clear the decimals.

26x^2 - 105x - 100 = 0

This doesn't look "factorable".........let's use the on-site solver. (And the quadratic formula!!)......

$${\mathtt{26}}{\mathtt{\,\times\,}}{{\mathtt{x}}}^{{\mathtt{2}}}{\mathtt{\,-\,}}{\mathtt{105}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{100}} = {\mathtt{0}} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = {\mathtt{\,-\,}}{\frac{\left({\mathtt{5}}{\mathtt{\,\times\,}}{\sqrt{{\mathtt{857}}}}{\mathtt{\,-\,}}{\mathtt{105}}\right)}{{\mathtt{52}}}}\\
{\mathtt{x}} = {\frac{\left({\mathtt{5}}{\mathtt{\,\times\,}}{\sqrt{{\mathtt{857}}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{105}}\right)}{{\mathtt{52}}}}\\
\end{array} \right\} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = -{\mathtt{0.795\: \!630\: \!993\: \!904\: \!701\: \!4}}\\
{\mathtt{x}} = {\mathtt{4.834\: \!092\: \!532\: \!366\: \!239\: \!8}}\\
\end{array} \right\}$$

And there are the two solutions .....  !!!

Thanks, CPhill.

I usually just google what I want a picture of. (In this case, I just googled "number line generator")

Then, if I want to edit the picture at all, I just use a paint program I have on my computer called paint.net

oh!Thanks for them CPhill!I can use them at school!only if the teacher doesnt take 'em away!

But thanks for the points too!

Good job, rosala....I have some sunglasses to share!!

4+4=8   ANSWER

You would use the arctan of 0.9063 (it is the inverse of the tangent, so it finds the angle's measurement):

$$\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}^{\!\!\mathtt{-1}}{\left({\mathtt{0.906\: \!3}}\right)} = {\mathtt{42.186\: \!016\: \!222\: \!452^{\circ}}}$$

So angle A is about 42 degrees.

The answer to "-6 + 9 * -1 - 4 * 4" would be -31.

To solve "-6 + 9 * -1 - 4 * 4" the first thing to do would be to multiply wherever there is a multiplication sign so that we can then add the remaining numbers together. Adding before multiplying would not follow the order of operations and would give us a completely different answer!

We can see that there are two multiplication signs in the equation and thus we need to multiply two pairs of numbers together:

-6 + 9 * -1 - 4 * 4

Let's start with "9 * -1":

9 * -1 = -9

Now for "4 * 4":

4 * 4 = 16

Now we can plug -9 and 16 back into the equation in place of the original pairs of numbers:

-6 + -9 - 16

Now all we have to do is add and subtract from the left to the right side of the equation. We can start this by finding "-6 + -9":

-6 + -9 = -15

Because both -6 and -9 are negative values, we can add them as if they were positive numbers, but we need to remember to place a "-" sign at the end of our answer.

Now to plug -15 back into the equation:

-15 - 16

Our final step to solving this equation is to subtract 16 from -15. Keep in mind that subtracting one number from another is the same as adding the negative value of that first number to the second number. In other words:

-15 - 16 = -15 + -16

We can just add -15 and -16 just (as we did with -6 and -9) to obtain a final answer of -31. Thus, our answer to the equation would be -31.

I hope I helped.

-pokemonfan58