Homework Help

Given the point A(1,20 and the slope 1/2 write the equation of the line.

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sodelete | Student, College Freshman | (Level 1) Honors

Posted May 9, 2011 at 11:48 PM via web

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Given the point A(1,20 and the slope 1/2 write the equation of the line.

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Wiggin42 | Student, Grade 11 | (Level 2) Valedictorian

Posted April 26, 2014 at 4:38 PM (Answer #5)

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We want a line through (1,20) and has the slope 1/2. 

Point slope is the easiest method here. Recall the formula: 

y - y1 = m(x - x1) where (x1,y1) is the point and m is the slope. 

Plug into this formula and you'll have your line. 

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justaguide | College Teacher | (Level 2) Distinguished Educator

Posted May 9, 2011 at 11:54 PM (Answer #1)

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The equation of a line passing through (x1, y1) and with a slope m is (y - y1)/(x - x1) = m

Here x1 = 1, y1 = 20 and the slope is 1/2

The equation of the line is:

(y - 20)/(x - 1) = 1/2

=> 2y - 40 = x - 1

=> x - 2y + 39 = 0

The equation of the line is x - 2y + 39 = 0

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giorgiana1976 | College Teacher | (Level 3) Valedictorian

Posted May 9, 2011 at 11:54 PM (Answer #2)

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This problem requires the point slope formula:

y - y1 = m(x - x1), where x1 and y1 are the coordinates of the given point A and m is the slope of the line.

We'll consider x1 = 1 and y1 = 2 (since the 0 key has the brackets symbol on it, we'll consider 0 as being an error of typing). The slope is m = 1/2.

y - 2 = (1/2)*(x - 1)

We'll remove the brackets:

y - 2 = x/2 - 1/2

y = x/2 + 2 - 1/2

y = x/2 + 3/2

The requested equation of the line, whose slope is m = 1/2 and it's passing through the point A(1,2), is: y = x/2 + 3/2.

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hala718 | High School Teacher | (Level 1) Educator Emeritus

Posted May 9, 2011 at 11:55 PM (Answer #3)

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Given the point ( 1, 20) and the slope m= 1/2

We need to write the equation of the line.

==> y-y1= m (x-x1)

==> y -20 = (1/2)( x-1)

==> y-20 = (1/2)x - 1/2

We will multiply by 2.

==> 2y - 40 = x -1

==> 2y -x - 39 = 0

==> x - 2y + 39 = 0

Then the equation of the line is: x - 2y + 39 = 0

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