SOLUTION: Write the slope-intercept equation for the line that passes through (-9,9) and is perpendicular to -9x-2y=10. Please show the steps
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-> SOLUTION: Write the slope-intercept equation for the line that passes through (-9,9) and is perpendicular to -9x-2y=10. Please show the steps
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Question 459794: Write the slope-intercept equation for the line that passes through (-9,9) and is perpendicular to -9x-2y=10. Please show the steps Found 2 solutions by nerdybill, Gogonati:Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website! Write the slope-intercept equation for the line that passes through (-9,9) and is perpendicular to -9x-2y=10. Please show the steps
.
Begin by finding the slope of:
-9x-2y=10
do this, by putting it into "slope-intercept" form:
-9x-2y=10
-2y=9x+10
y=(-9/2)x-5
slope is -9/2
.
Slope of our new line has be the "negative reciprocal" for it to be perpendicular.
(-9/2)m = -1
m = 2/9 (our new slope)
.
Plug the above slope and the point (-9,9) into the "point-slope" form:
y - y1 = m(x - x1)
y - 9 = (2/9)(x - (-9))
y - 9 = (2/9)(x + 9)
y - 9 = (2/9)x + 2
y = (2/9)x + 2 + 9
y = (2/9)x + 11 (this is what they're looking for)
You can put this solution on YOUR website! We first write the equation in slope-intercept form , as you see
the slope of the line is m1=-9/2, therefore the slope of the perpendicular line will be m2=2/9, because the perpendicular lines have negative reciprocals slopes.
Now we have to write the equation of the line with slope 2/9 that passes through the point (-9, 9):
, writing it in the slope-intercept form we get:
. See the graph below:
