SOLUTION: Find an equation of the line satisfying the given conditions. Through(-3,9),perpendicular to 2x+3y=21

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Question 1095985: Find an equation of the line satisfying the given conditions.
Through(-3,9),perpendicular to 2x+3y=21

Found 2 solutions by Boreal, MathTherapy:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
slope of 2x+3y=21
3y=-2x+21
y=(-2x/3)+7; slope is -2/3
perpendicular line has a slope that is the negative reciprocal, or in this instance 3/2
It goes through (-3, 9)
point slope formula
y-y1=m(x-x1), m is slope, (x1, y1) point
y-9=(3/2)(x+3), watch signs.
y=(3/2)x+9/2+9
y=(3x/2)+27/2
graph%28300%2C300%2C-20%2C20%2C-20%2C20%2C%28-2x%2F3%29%2B7%2C%283x%2F2%29%2B%2827%2F2%29%29

Answer by MathTherapy(10551) About Me  (Show Source):
You can put this solution on YOUR website!

Find an equation of the line satisfying the given conditions.
Through(-3,9),perpendicular to 2x+3y=21
2x + 3y = 21 
3x + 2y = c -------- Switching coefficients on variables, and changing the constant to c
3x - 2y = c -------- NEGATING coefficient on y
3x - 2y = 3(- 3) - 2(9) -------- Substituting GIVEN point (- 3, 9) to determine c
3x - 2y = - 9 - 18
highlight_green%28matrix%281%2C3%2C+3x+-+2y%2C+%22=%22%2C+-+27%29%29 ---- Required equation