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