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3 years ago

Please, help me I’m so dumb

Mathematics

1 answer:

Igoryamba3 years ago

7 0

Answer:

Step-by-step explanation:

You know that 9 = 10 - 1.

Then 9 of something is equal to 10 of it less one of it. Here, that "something" is four.

$\begin{array}{cl}9\times4&=10\text{ fours}-\boxed{1}\text{ four}\\&=\boxed{40}-4\\&=\boxed{36}\end{array}$

_____

<em>Comment on this math</em>

This illustrates a shortcut for multiplying by 9 that can be convenient for mental arithmetic. The idea is to multiply by 10, which just involves adding 0 (or moving the decimal point), then subtract the original number.

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I need help with question #2. ASAP. Anything is appreciated:)

DedPeter [7]

Y = 4/5x + 30

4/5 because the slope is 4 up, 5 right. 30 is the y-int

4 0

3 years ago

In the diagram, the radius of the outer circle is

JulijaS [17]

the value of x is 8 cm.

<u>Step-by-step explanation:</u>

Correct Question : In the diagram, the radius of the outer circle is 2x cm and the radius of the inside circle is 6 cm. The area of the shaded region is 220π cm2. What is the value of x? Enter your answer in the box.

We have ,

the area of a circle = πr²

the outer circle area = $\pi(2x)^2 =4\pi x^2$

the inside circle area = $\pi (6)^2= 36\pi$

According to Question,

the outer circle area - the inside circle area = he shaded region

⇒ $\pi (4x^2)-36\pi =220\pi$

⇒ $x^2-9 =55$

⇒ $x^2=64$

⇒ $x =\sqrt{64}=8$

Therefore , the value of x is 8 cm.

5 0

2 years ago

How can you tell if a fraction is a perfect square?

zimovet [89]

Answers: A fraction is a perfect square if it's reduced version (of an improper fraction if the number is greater than 1) has both numerator and denominator numbers that are perfect squares. IE: 25/36 is a perfect square because both 25 and 36 are perfect squares.

Step-by-step explanation:

So for example 5/25 is a perfect square but 2/5 wouldn't be a perfect square.

Tell me if this helped you

7 0

3 years ago

Show work on how you converted them. (also marking brainliest) <3

Dmitry_Shevchenko [17]

Answer:

1. 5700mg

2. 1000cm

3. 0.0453m

4. 37.5 kg/L

Step-by-step explanation:

1. 1gram (g) =1000milligrams(mg)

5.70×1000=5700mg

2. 1 m= 100cm

10×100=1000cm

3. 1000mm=1m

45.3/1000=0.0453m

4. 1000g=1kg

37.5/1000=0.0375

1000ml=1L

1ml= 1/1000= 0.001L

0.0375/0.001= 37.5 kg/L

8 0

2 years ago

Suppose Albers Elementary School has 32 teachers and Bothell Elementary School has 61 teachers. If the total number of teachers

Contact [7]

Answer: 31 teachers

Step-by-step explanation: let the number of teachers that teach in both school be x

By using venn diagram:

32 - x + x + 61 - x = 62

93 - x = 62

X = 93 - 62

X = 31

7 0

3 years ago