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Which statement explains how the lines 2x + y = 4 and y = one halfx + 4 are related?

They are parallel.
They are perpendicular.
They are the same line.
They are not related.

User Wilanda
by
5.9k points

2 Answers

4 votes

Answer: Yes, I too think the answer is "They are perpendicular."

User Sam Hokin
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5.0k points
4 votes

Answer:

They are perpendicular

Explanation:

To solve this problem .

we will convert the equations in slope intercept form.

Slope intercept form of equation is y = mx+c

where m is slope of line and c is y intercept.

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equation 1 is

2x+y = 4

=> y =4 - 2x or y = -2x + 4

comparing it with y = mx + c

m = -2 , c = 4

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equation 2 is y = one halfx + 4 ( one half is same as 1/2)

so equation is

y = x/2 +4

comparing it with y = mx + c

m = 1/2 , c = 4

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Now lets evaluate options

They are parallel. wrong option

For lines to be parallel slope should be same.

But here slope are different -2 and 1/2 .

Thus lines are not parallel.

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They are perpendicular. correct option

For lines to be perpendicular, product of slope should be equal to -1.

-2*1/2 = -1

we can see that product of slope should be equal to -1 .

Thus lines are perpendicular

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They are the same line. wrong option

For lines to be same both slope and y intercept should be same.

Y intercept is same but the slopes are different -2 and 1/2 .

Thus lines are not the same line.

__________________________________________

They are not related. wrong option

As we have found that the lines are perpendicular .

So this option is intuitively wrong

User Jason Navarrete
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6.4k points