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2 years ago

Solve the equation by completing the square. -9n^2+79+=-18n

1 answer:

6 0

Hello,
-9n²+79=-18n
==>9n²-18n-79=0
==>9(n²-2n+1-1)-79=0
==>9(n-1)²-88=0
==>[3(n-1)-2√22][3(n-1)+2√22]=0
==>3(n-1)=2√22 or 3(n-1)=-2√22
==>n-1=2/3*√22 or n-1=-2/3*√22
==>n=1+2/3*√22 or n=1-2/3*√22

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X/-9 =3 I dont understand this.

STatiana [176]

Final Answer: $x = -27$

Steps/Equations:

Question: $\frac{x}{-9} = 3$

Step 1: Move the negative sign to the left side.

$-\frac{x}{9} = 3$

Step 2: Multiply both sides by $3$ .

$-x = 3 * 9$

Step 3: Simplify $3 * 9$ to $27$ .

$-x = 27$

Step 4: Multiply both sides by $-1$ .

$x = -27$

~I hope I helped :)~

5 0

2 years ago

Read 2 more answers

Triangles DEF and D'E'F' are shown on the coordinate plane below: . . Triangle DEF and triangle D prime E prime F prime with ord

Brilliant_brown [7]

The correct answer is:
180° rotation.

Explanation: 
Comparing the points D, E and F to D', E' and F', we see that the x- and y-coordinates of each have been negated, but they are still in the same position in the ordered pair. 

A 90° rotation counterclockwise will take coordinates (x, y) and map them to (-y, x), negating the y-coordinate and swapping the x- and y-coordinates.

 A 90° rotation clockwise will map coordinates (x, y) to (y, -x), negating the x-coordinate and swapping the x- and y-coordinates.

Performing either of these would leave our image with a coordinate that needs negated, as well as needing to swap the coordinates back around.

This means we would have to perform the same rotation again; if we began with 90° clockwise, we would rotate 90 degrees clockwise again; if we began with 90° counter-clockwise, we would rotate 90 degrees counterclockwise again. Either way this rotates the figure a total of 180° and gives us the desired coordinates.

4 0

2 years ago

Read 2 more answers

Find the equation of a line with slope 1/2 and y intercept -1

Mrac [35]

If you use slope-intercept form, Y =mx+b

m is equal to the slope,
and b is the y intercept.

Y= (1/2)x+ (-1)

or
Y = (1/2)x-1

4 0

2 years ago

I need 50 gallons of milk replacer for calves and the powder mixture says it's 6.25 oz for 5 gallons how many oz of powder do I

zubka84 [21]

Answer:

62.5 oz

Step-by-step explanation:

We can use the ratio proportion method:

x:50::6.25:5

x = (50x6.25)/5

OR a more simple method is to do this:

5 gallons of milk require 6.25 oz. How many oz of powder do I need to get 10x that amount? Since 50 is 10x5, you do the same thing for 6.25, and get 62.5

3 0

1 year ago

The area of a rectangle is 243.9 m2. If the length is 15 m, what is the perimeter of the rectangle?

patriot [66]

Step-by-step explanation:

Given

Area of rectangle (A) = 243.9 m²

Length (L) = 15 m

first calculating the breadth (b)

We know

L * b = A

15 * b = 243.9

b = 243.9/ 15

b = 16.26 m

Now

Perimeter (p)

= 2 ( L + b)

= 2 ( 15 + 16.29)

= 62.58 m

Hope it will help

3 0

2 years ago