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3 years ago

There is a 4 digit number that when multiplied by 4 is the reverse.

Mathematics

2 answers:

cestrela7 [59]3 years ago

7 0

2178 that the answer

mote1985 [20]3 years ago

6 0

Answer:

The answer is 2178, if you multiply it by 4, you would get 8717

Step-by-step explanation:

HERE ARE THE STEPS IF YOU NEED THEM!!

1. Lets say the number is written as ABCD (1000a+100b+10c+d).

2.Multiplying it by 4, gives you DCBA (1000d+100c+10b+a)

3. By divisibility of 4, BA is a two-digit number divisible by 4.

4.Now, the largest possible value of ABCD is 2499, because anything more will result in a five digit number when multiplied by 4.

5. Out of the two possibilites 1 and 2 for A, [3] follows that A is even, so 2.

6. From [5], D is either 8 or 9. However, since D times 4 would end in 2, D is 8.

7. Using [2], 4000a+400b+40c+4d = 1000d+100c+10b+a, which would simplify to 2c-13b = 1 after substituting A = 2 and D = 8.

8.The only possible value of (b,c) where they would both be single digit integers is (1,7). Also to note from [3], B is odd. And from [4], B is either 1 or 3.

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A right triangle has legs that measure 7 cm and 6 cm. What is the length of the hypotenuse in meters?

dalvyx [7]

<h2>Greetings!</h2>

Answer:

$\sqrt{85} or 9.22$

Step-by-step explanation:

You need to remember the following equation:

$a^{2} + b^{2} = c^{2}$

Where a and b is the lengths of the two sides and c is the hypotenuse.

So simply plug these values into this:

$6^{2} + 7^{2} = h^{2}$

36 + 49 = h^2

36 + 49 = 85

So the hypotenuse is the square root of 85:

$\sqrt{85} = 9.22$

<h2>Hope this helps!</h2>

7 0

2 years ago

Find the area of the figure<br>a) 114cm2<br>b) 350cm2<br>c) 418cm2<br>d) 447cm2<br>

uysha [10]

Answer: I thin it's A because you just multiply 19*6

Step-by-step explanation:

4 0

3 years ago

from the top of a tree the angle of depression of a rock on the ground is 49 degrees. If the tree is 18.5 m tall, how far is the

Rashid [163]

Answer:

Step-by-step explanation:

If you were to sit in the very top of said tree and look directly straight, your line of vision would be parallel to the ground. The angle of depression is in between your line of vision and the rock. When you look down at the rock, your line of vision to the rock is a transversal between the 2 parallel lines. With this being the case, the angle of depression is alternate interior with the angle made on the ground from the rock to the top of the tree. See the illustration I attached below.

We are looking for the distance on the ground between the tree and the rock, which we will call x. The side opposite the reference angle is the height of the tree and the side adjacent to the reference angle is x. Side opposite over side adjacent is the tangent ratio. Therefore,

$tan(49)=\frac{18.5}{x}$ and