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1 year ago

(09.02)

Mathematics

1 answer:

Ivenika [448]1 year ago

4 0

Answer:

4th option

Step-by-step explanation:

x² - 2x - 3 = 0 ( add 3 to both sides )

x² - 2x = 3

using the method of completing the square

add ( half the coefficient of the x- term )² to both sides

x² + 2(- 1)x + 1 = 3 + 1

(x - 1)² = 4

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-4x + 12 = 8<br><br> Solve for x

jasenka [17]

Answer:

x=1

Step-by-step explanation:

1.Move the constant to the right

2. Calculate

3. Divide both sides

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2 years ago

Anna is playing a word game with tiles shaped like triangles. She needs to make a word with only those that appear to be right t

PIT_PIT [208]

B) FELT is the correct answer

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3 years ago

Read 2 more answers

Find the probability. Round your answer to the nearest hundredth, if needed.

padilas [110]

Answer:

0.2

Step-by-step explanation:

Given:

Total number of students = 20

Number of students who have brown hair = 12

Number of students who have blonde hair = 4

Number of students who have red hair = 3

Number of students who have black hair = 1

To find:

Probability of randomly selecting a blonde-haired student from the classroom.

Solution:

Probability refers to chances of occurring of some event.

Probability = Number of favourable outcomes/ Total number of outcomes

Number of favourable outcomes ( Number of students who have blonde hair ) = 4

Total number of outcomes = 20

So,

Probability of randomly selecting a blonde haired student from the classroom = $\frac{4}{20}=\frac{1}{5}=0.2$

5 0

2 years ago

Bob has 7 oranges, 10 plums and 4 pears in a bowl. He can choose: an orange and a plum or a plum and a pear or an orange, a plum

atroni [7]

In statistics the word "and" symbolized for multiplaction operation and the word "or" symbolized addition operation. so the number of ways can bob choose a fruit from the bowl is :

P = ( 7 x 10 ) + ( 10 x 4 ) + (4 x 7)
P = 138 ways he can choose a fruit from the bowl

7 0

3 years ago

One of the loudest sounds in recent history was that made by the explosion of Krakatoa on August 26-27, 1883. According to barom

liraira [26]

Answer:

150.51 dB

Step-by-step explanation:

Data provided in the question:

decibel level of sound at 161 km distance = 180 dB

d₁ = 161 km

d₂ = 4800 km

I₁ = 180 db

The formula for intensity of sound is given as:

I = $10\log(\frac{I_2}{I_1})$

and the relation between intensity and distance is given as:

I ∝ $\frac{1}{d^2}$

Id² = constant

thus,

I₁d₁² = I₂d₂²

$\frac{I_2}{I_1}=\frac{d_1}{d_2}$

therefore,

I = $10\log(\frac{d_1}{d_2})^2$

I = $10\times2\times\log(\frac{161}{4,800})$

I = 20 × (-1.474)

I = -29.49

Therefore,

the decibel level on Rodriguez Island, 4,800 km away

= 180 - 29.49

= 150.51 dB

8 0

2 years ago