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Write the equation of the line that passes through the points (8, –1) and (2, –5) in standard form, given that the point-slope form is y + 1 = (x – 8).

User Jthegedus
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2 Answers

18 votes
18 votes

Answer:

The answer is 2x + -3y = 19

Explanation:

I Got It Right Instruction on edge

User Tyler Lee
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13 votes
13 votes

Answer:

A linear equation in the standard form is written as:

y = a*x +b

where a is the slope and b is the y-intercept.

If we know that the line passes through the points (a, b) and (c, d), then the slope can be written as:

a = (d - b)/(c - a)

So we know that our line passes through the points (8, -1) and (2, -5)

then the slope will be:

a = (-5 - (-1) )/(2 - 8) = (-4/-6) = 2/3

Then our line is something like:

y = (2/3)*x + b

to find the value of b, we can use the fact that we know that our line passes through the point (2, -5)

this means that when x = 2, we must have y = -5

replacing these values in the equation we get:

-5 = (2/3)*2 + b

-5 = 4/3 + b

-5 - 4/3 = b

-15/3 - 4/3 = b

-19/3 = b

then the equation is:

y = (2/3)*x - 19/3

(in the question you wrote the point-slope form, but you can see that it does not work for the second point, so there may be a mistake there, as the slope is missing)

The actual equation in the point-slope form is:

y + 1 = (2/3)*(x - 8)

User Rich Drummond
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3.3k points