All categories

2 years ago

What is the value of the rational expression 2x^2+5x+9/x^2+2x-1 when x=-2

Mathematics

2 answers:

anygoal [31]2 years ago

6 0

Answer: -7

Step-by-step explanation:

Sergio039 [100]2 years ago

5 0

Answer:

The value of the Rational expression when $x=-2$ is: $-7$

Step-by-step explanation:

For this exercise is important to remember:

When a negative number is raised to an even power, the result will be positive.
The multiplication of signs:

$(+)(+)=+\\(-)(-)=+\\(-)(+)=-$

Then, given the following Rational expression:

$\frac{2x^2+5x+9}{x^2+2x-1}$

You need to follow these steps in order to find its value when $x=-2$ :

1. Substitute the given value of "x" ( $x=2$ ) into the expression:

$\frac{2(-2)^2+5(-2)+9}{(-2)^2+2(-2)-1}$

2. Evaluate and simplify:

$\frac{2(4)+5(-2)+9}{4+2(-2)-1}=\frac{8-10+9}{4-4-1}=\frac{7}{-1}=-7$

You might be interested in

This is my math geometry... What does x equal on the shape to the right?

andrezito [222]

Answer:

x=12

Step-by-step explanation:

It is a textbook 3:4:5 triangle. The hypotenuse is 15 (5*3), and the base is 9 (3*3). Since they both share a common factor of 3, the 3rd side would be 4*3, which is 12.

5 0

2 years ago

Four less than three times a number is three more than two times the number. What is the number?

MAXImum [283]

Hello!

Say that n is the number. There are two parts to this statement. The first part is "four less than three times a number", and the second is "is three more than two times the number. An expression fitting the first part will go on the left side of the equation, and the second part will go on the right.

Look at the first part. "Four less than three times a number". The first thing being done here is the three times a number. This would be 3n, as it is 3 times n. Now, there is the four less part. You would therefore have to subtract 4 from 3n, to get 3n - 4.

Now the second part. "Is three more than two times the number". The first thing being done here is the two times the number. That would be 2n. The next is "is three more than". If the other side is three more than 2n, then you must add 3 to 2n to make them equivalent. Therefore, it would be 2n + 3.

Now, set them equal to each other, and solve.

3n - 4 = 2n + 3

3n - 2n = 3 + 4

n = 7

Therefore, your number is 7.

Hope this helps!

5 0

2 years ago

The table below represents a linear function f(x) and the equation represents a function g(x): x f(x) −1 −7 0 −1 1 5 g(x) g(x) =

astra-53 [7]

Question A:

Rewriting the table for f(x):

x -1 0 1
f(x) -7 -1 5

Notice that for every increase of one unit in 'x', there are an increase 6 units on f(x). Hence, the gradient of the slope of f(x) is 6.

g(x) = 5x - 4 ⇒ This function follows the general form of the straight line equation, y = mx + c, where 'm' is the gradient and 'c' is the y-intercept.
Hence, the gradient of the slope of g(x) is 5.

The slope of f(x) is steeper than the slope of g(x).

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

Question B:

The y-intercept is the value of y where a straight line crosses the y-axis (or when x is zero).

From the table of f(x), the y-intercept is -1 (this is the value of 'y' when 'x' is zero)

From the given function g(x) = 5x - 4, the y-intercept is -4.

f(x) has a greater y-intercept.

8 0

3 years ago

James wants to send two gifts by mail. one package weighs 2 3/4 pounds. the other package weighs 1 3/4 pounds. what is the total

Taya2010 [7]

Answer:

4.5 pounds

Step-by-step explanation:

Convert them both to improper equations.

2 3/4 = 11/4

1 3/4 = 7/4

Then add.

11/4 + 7/4 = 18/4

Then simplify.

18/4 = 4 2/4 = 4.5

7 0

2 years ago

Read 2 more answers

Find the measure of each angle in the triangle.

makvit [3.9K]

<A +(5x+6) + (2x+1) + (6x+4) = 180°
13x = 180°-11° ==> 13x 169° and x =169/13 =13°

8 0

2 years ago