Name: Lori
Who is asking: Student
Level: Secondary

Find an equation of the line parallel to the given line containing the given point. x + y = 2; (1,2) We know parallel line have the same slope and we know the answer y = -x + 3.

How did they get to that point? Help. Thank you

Hi Lori,

If you write the equation of a line in the form

y = mx + b

then m is the slope. The line you have, x + y = 2 can be written y = -x + 2 and thus it has slope -1.

As you noticed the line you want must also have slope -1 and its equation can be written y = -x + b. All that remains is to find b. This is where you use the fact that the line you want containt the point (1,2). Thus (1,2) must satisfy the equation y = -x + b. Substitute (1,2) into the equation and solve for b.

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