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3 years ago

Can someone understand this i know its substitution for sure if i dont get wrong

Mathematics

1 answer:

svlad2 [7]3 years ago

7 0

4x - y = 3

y = 2x + 13

Substitute the second equation into the first equation:

4x - y = 3 [since y = 2x + 13, you can substitute (2x + 13) for "y" in the equation]

4x - (2x + 13) = 3 Distribute/multiply - into (2x + 13)

4x - 2x - 13 = 3

2x - 13 = 3 Add 13 on both sides

2x = 16 Divide 2 on both sides

x = 8

Now that you know x = 8, plug it into one of the equations to find y

y = 2x + 13

y = 2(8) + 13

y = 16 + 13

y = 29

x = 8, y = 29 or (8, 29)

[proof]

4x - y = 3

4(8) - 29 = 3

32 - 29 = 3

3 = 3

y = 2x + 13

29 = 2(8) + 13

29 = 16 + 13

29 = 29

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Sub 4 in 3
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Hope it's the way you wanted it

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The mean of a sequence of numbers is the average.

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So, we have:

$\mathbf{mn = m_1 \times n_1 + m_2 \times n_2}$

Hence, the true statement is: $\mathbf{mn = m_1 \times n_1 + m_2 \times n_2}$

Read more about mean and averages at:

brainly.com/question/16217700

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See the graph

<h2>Explanation:</h2>

Remember to write complete questions in order to get good and exact answers. Here you haven't provided any option, but it's easy to plot this point on a coordinate system in order to know the location of the movie theater. We know that this theater is at the point:

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x < 0 for the x-values to the left of the origin.

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<h2>Learn more:</h2>

Cartesian coordinate system: brainly.com/question/2141683

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