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Rasek [7]
2 years ago
12

A little difficult question for me, it is multiple choice answer but my teacher taught this before the break. If anyone could he

lp me that would be wonderful.

Mathematics
1 answer:
Sever21 [200]2 years ago
7 0
<h3>Answer: Choice D</h3>

Divide both sides of the first equation by 7, then add the result to the second equation

=======================================================

Explanation:

We can multiply both sides of an equation by the same number and the equation will be equivalent to the original.

For example, if we had  x = 5, then we could get 2x = 10 after multiplying both sides by 2. The reason they are equivalent equations is because the same x value is the solution for both equations.

We can also divide both sides of an equation by the same number and the two equations would be equivalent. We can go from 2x = 10 back to x = 5 when we divide both sides by 2.

----------

If we divide both sides of 7x - 21y = 14 by 7, then we end up with x - 3y = 2. Simply divide each term (7x,  -21y, and 14) by 7.

Because 7x-21y=14 and x-3y=2 are equivalent, this means we can replace the "7x-21y=14" with "x-3y=2"

--------

The new system would be

x-3y = 2

2x+3y = 11

From here you add straight down. Doing so will have the y terms add to -3y+3y = 0y = 0. After this point the y terms are eliminated and you can solve for x just like with any other equation of one variable.

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Two persons start running simultaneously from a certain point, one towards south and another towards east. After 2 hours, the di
Volgvan

The Pythagorean theorem is sometimes known as Pythagoras' theorem. The speed of the faster person is 40 kmph.

<h3>What is Pythagoras' theorem?</h3>

The Pythagorean theorem, sometimes known as Pythagoras' theorem, is a basic relationship between the three sides of a right triangle in Euclidean geometry. The size of the square whose side is the hypotenuse is equal to the sum of the areas of the squares on the other two sides, according to this rule.

Let the speed of one person be represented by x, then the speed of the other person, if the speed of the second person is 75% of the first.

  • Speed of first-person = x
  • Speed of second-person = 75% of Speed of first-person = 0.75x

Now, the distance covered by two persons in 2 hours is,

  • Distance covered by the first-person = x × 2 = 2x
  • Distance covered by the second-person = 0.75x × 2 = 1.5x

Since one person runs towards the south and another towards the east. Therefore, will form a 90° angle between their directions.

Now, the distance between the two after two hours is 100 km, therefore, we can write,

(2x)² + (1.5x)² = 100²

4x² + 2.25x² = 10000

6.25x² = 10000

x² = 10000/6.25

x² = 1600

x = √1600

x = 40

Hence, the speed of the faster person is 40 kmph.

Learn more about Pythagoras' Theorem here:

brainly.com/question/14461977

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6 0
1 year ago
Solve similar triangles (advanced)<br> Solve for x<br> x=?
lesya692 [45]

Answer:

x = 1.2

Step-by-step explanation:

AD/AB = DE/BC (Similarity Theorem)

AD = 6 + 4 = 10

AB = 6

DE = 2

BC = x

Plug in the values

10/6 = 2/x

Cross multiply

10*x = 2*6

10x = 12

Divide both sides by 10

x = 12/10

x = 1.2

8 0
3 years ago
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vampirchik [111]

Answer:

$19.58+$5.00 = $24.58

Step-by-step explanation:

3 0
3 years ago
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Please help me with this!!
Kaylis [27]

Answer:

C. 72

Step-by-step explanation:

So imagine every straight line you see equals to 180 degrees, so given one side of the angle...180 - 108 = 72

7 0
3 years ago
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Which correctly names a point, line, or plane in the figure?
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The answer is B; at least, I am pretty sure that's the answer.
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