<img src="https://tex.z-dn.net/?f=7%20%2B%20%28%20-%204%29" id="TexFormula1" title="7 + ( - 4)" alt="7 + (

All categories

lisabon 2012 [21]

3 years ago

e" class="latex-formula">

Mathematics

1 answer:

gulaghasi [49]3 years ago

7 0

The first step for solving this expression is to know that when there is a "+" in front of the parenthesis,, then the expression remains the same.
7 - 4
Now we will simply subtract the numbers to find our final answer.
3
Let me know if you have any further questions.
:)

You might be interested in

Are these a rational function?

Thepotemich [5.8K]

158.:$?&duck icy blue

5 0

3 years ago

Which equation represents the equation of the parabola with focus (-3 3) and directrix y=7?

Artemon [7]

Answer:

The equation $y=\frac{-x^2-6x+31}{8}$ represents the equation of the parabola with focus (-3, 3) and directrix y = 7.

Step-by-step explanation:

To find the equation of the parabola with focus (-3, 3) and directrix y = 7. We start by assuming a general point on the parabola (x, y).

Using the distance formula $d = \sqrt {\left( {x_1 - x_2 } \right)^2 + \left( {y_1 - y_2 } \right)^2 }$ , we find that the distance between (x, y) is

$\sqrt{(x+3)^2+(y-3)^2}$

and the distance between (x, y) and the directrix y = 7 is

$\sqrt{(y-7)^2}$ .

On the parabola, these distances are equal so, we solve for y:

$\sqrt{(x+3)^2+(y-3)^2}=\sqrt{(y-7)^2}\\\\\left(\sqrt{\left(x+3\right)^2+\left(y-3\right)^2}\right)^2=\left(\sqrt{\left(y-7\right)^2}\right)^2\\\\x^2+6x+y^2+18-6y=\left(y-7\right)^2\\\\x^2+6x+y^2+18-6y=y^2-14y+49\\\\y=\frac{-x^2-6x+31}{8}$