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3 years ago

If equation one is mutiplied by 2 and then the equations are added the result is 2x+y=3 X-2y=-1

Mathematics

1 answer:

zloy xaker [14]3 years ago

8 0

Question:

2x + y = 3, x - 2y = –1.

If equation one is multiplied by 2 and then the equations are added, the result is _____.

(A) 3x = 2

(B) 3x = 5

Answer:

Option C:

5x = 5

Solution:

Given equations are

2x + y = 3 – – – – (1)

x – 2y = –1 – – – – (2)

Let us first multiply equation (1) by 2, we get

(1) × 2 ⇒ 4x + 2y = 6 – – – – (3)

Now, add equation (3) to equation (2).

⇒ x – 2y + 4x + 2y = –1 + 6

Combine like terms together.

⇒ x + 4x – 2y + 2y = –1 + 6

⇒ 5x = 5

So, if equation one is multiplied by 2 and then the equations are added, the result is 5x = 5.

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3 years ago

Which set is closed under subtractionWhich answer choice shows that the set of irrational numbers is not closed under addition

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2 years ago

A property sells for $140,000 two years after it was purchased. If the annual appreciation rate is 6%, how much did the original

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