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3 years ago

Use the quadratic formula to solve the equation x2+7x

Mathematics

1 answer:

monitta3 years ago

4 0

The solution of the equation x2+7x is 0, -7 using the quadratic formula.

Step-by-step explanation:

x2 + 7x = 0

-b ± √ b2 - 4(ac)/ 2a

substitution,

a = 1, b = 7, c = 0

= -7 ± √(7)2 - 4(1 x 0) / 2 x 1

= - 7 ± 7 / 2

x = 0 , -7

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liq [111]

Answer:

x = 13.5 units

Step-by-step explanation:

Segment drawn to join the two sides of the triangle is parallel to third side of the triangle.

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3 years ago

The letters of ALABAMA and LAMB were placed on separate slips of paper and put into two different bags.

labwork [276]

Answer:

45%

Step-by-step explanation:

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2 years ago

If x + 10 = 70, what is x? Α. 40 B. 50 C. 60 D. 70 E. 80

Helen [10]

Answer:

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2 years ago

Read 2 more answers

Frank has devised a formula for his catering business that calculates the number of meat balls he needs to prepare the formula i

ira [324]

Answer:

96 meatballs are required

Step-by-step explanation:

We know that the formula for he catering business is

$m=4a+2c$

Where

c= the number of children, m=the number of meat balls, a= the number of adults

So if $c = 8$ and $a = 20$ then

$m = 4(20) + 2(8)$

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Finally 96 meatballs are required for the party

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3 years ago

Emergency 911 calls to a small municipality in Idaho come in at the rate of one every two minutes. Assume that the number of 911

nordsb [41]

Answer: a) 30, b) 0.2138, c) 0.0820

Step-by-step explanation:

Since we have given that

X be the number of calls in 1 hour = 60 minutes

Rate of one call every two minutes.

$\lambda=\dfrac{1}{2}$

(a) What is the expected number of 911 calls in one hour?

$\lambda=\dfrac{1}{2}\times 60=30$

(b) What is the probability of three 911 calls in five minutes? If required, round your answer to four decimal places.

$\lambda=\dfrac{1}{2}\times 5=2.5$

Number of calls = 3

So, P(X=3) is given by

$P(X=3)=\dfrac{e^{-\lambda}\lambda^x}{x!}\\\\P(X=3)=\dfrac{e^{-2.5}\times (2.5)^3}{3!}\\\\P(X=3)=0.2138$

(c) What is the probability of no 911 calls during a five-minute period? If required, round your answer to four decimal places.

$P(X=0)=\dfrac{e^{-2.5}(2.5)^0}{0!}=0.0820$

Hence, a) 30, b) 0.2138, c) 0.0820

4 0

3 years ago

Use the quadratic formula to solve the equation x2+7x​

Use the quadratic formula to solve the equation x2+7x