SOLUTION: I need help with this question: find the equation of the straight line: which passes through (-7,4) and makes an angle of 143(deg)8(min) with the X-axis. I know the equatio

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Question 479093: I need help with this question:
find the equation of the straight line:
which passes through (-7,4) and makes an angle of 143(deg)8(min) with the X-axis.
I know the equation will look like either ax+by=c or y=mx+n
and i understand y-y1=m(x-x1) = y-4=m(x+7)
how do you convert the angle (143.133) to =m?

Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website!
y=m*x + n will be the type of equation
m the slope can be calculated by angle;
m = tan(143.133)=-0.75
tan(angle) * startPoint_X + n = startPoint_Y
so n = startPoint_Y - (tan ( angle) * startPoint_X )
n= 4-(-0.75*-7)
n=5.25
y=-0.75x-5.25+4
y=-0.75x-1.25 is the required equation.
Draw the line to check if the point lies on the derived line
CHECK

m.ananth@hotmail.ca