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lawyer [7]
2 years ago
15

What is the answer for 2n^2-8n=-9 ?

Mathematics
1 answer:
lbvjy [14]2 years ago
5 0

2n^2-8n=9

divide by 2

2(n^2-4n) =9

add (4/2)^2 =4 to each side  completing the square

(n^2-4n+4 ) =9/2+4

(n-2)^2 = 9/2+8/2

(n-2)^2 =17/2

take the square root of each side

n-2 = +-sqrt(17/2)

add 2 to each side

n = 2+- sqrt (17/2)

Answer:2+ sqrt (17/2),2- sqrt (17/2)


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Help please this is due soon! I need you to show the work as well <3 pic below
Dafna1 [17]

Answer:

perimeter: 4x+2 area: x^2+x

Step-by-step explanation:

for perimeter, you add x+x+x+x+1+1, which is 4x+2

for area, you multiply x*x+1, which would be x^2+x

7 0
3 years ago
Verify that [tan(theta) + cot(theta)]^2 = sec^2(theta) + csc^2(theta)
Wittaler [7]

(tanθ + cotθ)² = sec²θ + csc²θ

<u>Expand left side</u>: tan²θ + 2tanθcotθ + cot²θ

<u>Evaluate middle term</u>: 2tanθcotθ = 2*\frac{sin\theta}{cos\theta}*\frac{cos\theta}{sin\theta} = 2

⇒ tan²θ + 2+ cot²θ

= tan²θ + 1 + 1 + cot²θ

<u>Apply trig identity:</u>  tan²θ + 1 = sec²θ

⇒ sec²θ + 1 + cot²θ

<u>Apply trig identity:</u>  1 + cot²θ = csc²θ

⇒ sec²θ + csc²θ

Left side equals Right side so equation is verified


7 0
3 years ago
−12d+58=38d−1116 what does p=
weeeeeb [17]

Answer:

d= 587/25, d=23.48

Step-by-step explanation:

8 0
2 years ago
A cheetah spots a gazelle 300 meters away. The cheetah begins to chase the gazelle at a rate of 18 meters per second at the same
Rina8888 [55]
The cheetah runs 2 meters/sec faster than the gazelle.  Eventually the cheetah will overcome the gazelle.  Since distance = rate times time, time = distance/rate.

Thus, 

300 meters / (2 meters/sec) = 150 sec = 2 min 30 sec
8 0
3 years ago
Find an equation for the line that passes through the point (-4, 10) and (16, -2)
Crank

Answer:

y = 3/5x + 62/5

Step-by-step explanation:

Equation of a line with two points is

m = y - y_1 / x - x _1

m = y_2 - y_1 / x_2 - x _1

Equating both

y - y_1 / x - x_1 = y_2 - y_1 / x_2 - x_1

Using what we are provided with

(-4 , 10)(16 , -2)

x_1 = -4

y_1 = 40

x_2 = 16

y_2 = -2

Imputing the values

10 - (-2) / 16 - (-4) = y - 10 / x - (-4)

10 + 2 /16 + 4 = y - 10 / x + 4

12 / 20 = y - 10 / x + 4

Lets cross multiply

12 ( x + 4) = 20(y - 10)

Open the brackets

12x + 48 = 20y - 200

12x + 48 + 200 = 20y

12x + 248 = 20y

Following this equation of line

y = mx + C

20y = 12x + 248

Let's divide through by 20 to get y.

20y / 20 = 12x + 248 / 20

y = 12x + 248 / 20

We can separate it by

y = 12x / 20 + 248 / 20

y = 3/5x + 62/5

Therefore, the equation of the line is

y = 3/5x + 62/5

3 0
3 years ago
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