The question with the fire truck

Simplify the rational expression. state any restrictions on the variable. n^4-11n^2+30/n^4-7n^2+10

Andrej [43]

For this case we have the following expression:
 $\frac{n ^ 4-11n ^ 2 + 30}{ n ^ 4-7n ^ 2 + 10} 

$
 We are going to make the following change of variables:
 $x = n ^ 2
$
Rewriting the expression we have:
 $\frac{(x ^ 2-11x + 30)}{(x ^ 2-7x + 10)} 

$
Factoring the expression we have:
 $\frac{(x-5) (x-6)}{(x-5) (x-6)} 
$
Canceling similar terms we have:
 $\frac{x-6}{x-2} 
$
Returning the change we have:
 $\frac{n ^ 2-6}{n ^ 2-2} 

$
 The resctrictions of the function are those that make the denominator equal to zero.
We have then:
 $n ^ 2-2 = 0

n = +/- \sqrt{2} 
$
 Answer:
The simplified expression is:
 $\frac{n ^ 2-6}{n ^ 2-2}$
The restrictions are:
 $n = \sqrt{2} 
$
$n = - \sqrt{2}$

7 0

2 years ago

If -xy – 5+ y^2+ x^2= 0 and it is known that dy/dx= y-2x/-x+2y, find all

sleet_krkn [62]

Answer:

There is no point of the form (-1, y) on the curve where the tangent is horizontal

Step-by-step explanation:

Notice that when x = - 1. then dy/dx becomes:

dy/dx= (y+2) / (2y+1)

therefore, to request that the tangent is horizontal we ask for the y values that make dy/dx equal to ZERO:

0 = ( y + 2) / (2 y + 1)

And we obtain y = -2 as the answer.

But if we try the point (-1, -2) in the original equation, we find that it DOESN'T belong to the curve because it doesn't satisfy the equation as shown below:

(-1)^2 + (-2)^2 - (-1)*(-2) - 5 = 1 + 4 + 2 - 5 = 2 (instead of zero)

Then, we conclude that there is no horizontal tangent to the curve for x = -1.

3 0

2 years ago

The sum of the lengths of two opposite sides of the circumscribed quadrilateral is 12 cm, the length of a radius of the circle i

nasty-shy [4]

Answer:

60cm^2

Step-by-step explanation:

We assume that is a circumscribing quadrilateral, rather than one that is circumscribed. It is also called a "tangential quadrilateral" and its area is ...

K = sr

where s is the semi-perimeter, the sum of opposite sides, and r is the radius of the incircle.

K = (12 cm) (5cm) = 60 cm²

_____

A quadrilateral can only be tangential if pairs of opposite sides add to the same length. Hence the given sum is the semiperimeter.

8 0

2 years ago

HELP PLEASE I NEED TO GET IT DONE BECAUSE ILL BE WITH MY FAMILY AT THANKSGIVING TOMORROW

dalvyx [7]

Answer:

6

Step-by-step explanation:

Straight line is 180

square = right angle=90

180-90=90

5x+(x+54)=90

6x+54=90

6x=36

x=6

Hope this helps :D

6 0

2 years ago

if there is 7 billion people on earth then the corona virus kills 1/100 of the population after that thanos snaps how much of th

Vlada [557]

When Thanos snaps he wipes out have of the universe. That doesn't mean half of every population on every single planet. That means half of the universe as a whole. This question does not have an exact answer because though its unlikely, it is possible that when Thanos snaps, nobody on Earth dies.

5 0

2 years ago