kitty<3

La calculatora es muy conveniente para este:)

(-1/5) (-7/2) (-1/3)

= (-1/5) * (-7/2) * (-1/3)

$${\mathtt{\,-\,}}\left({\frac{{\mathtt{1}}}{{\mathtt{5}}}}\right){\mathtt{\,\times\,}}{\mathtt{\,-\,}}\left({\frac{{\mathtt{7}}}{{\mathtt{2}}}}\right){\mathtt{\,\times\,}}{\mathtt{\,-\,}}\left({\frac{{\mathtt{1}}}{{\mathtt{3}}}}\right) = {\mathtt{\,-\,}}{\frac{{\mathtt{7}}}{{\mathtt{30}}}} = -{\mathtt{0.233\: \!333\: \!333\: \!333\: \!333\: \!3}}$$

Si, se puede. 

Por ejemplo, 

$${\sqrt[{{\mathtt{{\mathtt{\pi}}}}}]{{\mathtt{4}}}} = {\mathtt{1.554\: \!682\: \!275\: \!482\: \!100\: \!1}}$$ 

Y:

$${{\sqrt{{\mathtt{2}}}}}^{\,{\mathtt{\pi}}} = {\mathtt{2.970\: \!686\: \!423\: \!552\: \!02}}$$

Escribe atan( ) para tagente inversa, o usa el boton "2nd", entonces "atan".

Actually, Dragonslayer, my answer was correct. I just thought I'd add in a note to you as well:)

~Kitty

Since x = -4, simply plug in -4 into the expression 9x:

9x

= 9 * x

= 9 * -4

= -36

Edit: dragonslayers can be fast sometimes! No worries, DS.

For example, you have a system of equations with two variables. You would set one of the  variables (for example, x) in one equation equal to something of the other variable (y). Then you would plug that something of y into the second equation and solve for y. Finally, you would plug in the value you got for y into one of the equations to find x. 

Example below: 

y = x + 2

x + y = 12

Plug in (x+2) into the second equation as x:

x + (x+2) = 12

Now solve for x:

2x + 2 = 12

2x = 10

x= 5

Now plug in 5 for x in the first equation to solve for y:

y = 5 + 2

y = 7

4x + 5 = 2x- 7

Subtract 2x from both sides:

2x +5 = -7

Now subtract 5 from both sides:

2x = -12

Divide by 2 to get the value of x. 

x = -6

The tablecloth is a square, so the area, 30ft², is the lengths of the sides squared. 

Therefore, one side's length is the square root of 30.

$${\sqrt{{\mathtt{30}}}} = {\mathtt{5.477\: \!225\: \!575\: \!051\: \!661\: \!1}}$$

Now round that to the nearest tenth for your answer in feet.

You would set up this problem as:

36=x * 720

divide 36 by 720:

x= $${\frac{{\mathtt{36}}}{{\mathtt{720}}}} = {\frac{{\mathtt{1}}}{{\mathtt{20}}}} = {\mathtt{0.05}}$$

Convert the decimal answer 0.05 to percent by multiplying it by 100. 

x = 0.05 * 100

= 5 percent

Alvarez tiene razón:)

También, si él preguntó como poner fracciones en la calculadora:

Usa los paréntesis.

Por ejemplo,

una cuarta = (1/4) = $$\left({\frac{{\mathtt{1}}}{{\mathtt{4}}}}\right)$$

y cinco cuartas = (5/4) = $$\left({\frac{{\mathtt{5}}}{{\mathtt{4}}}}\right)$$   o  1+(1/4) = $${\mathtt{1}}{\mathtt{\,\small\textbf+\,}}\left({\frac{{\mathtt{1}}}{{\mathtt{4}}}}\right)$$