How would I go about writing the equation of the line which passes through (2, –3) and is perpendicular to y = 4x + 7 in standard form ?

Question

anonymous · Answer

First, consider the slope of the line y=4x+7. What will be the slope of a line perpendicular to it?

anonymous · Answer

slope of  y = 4x + 7 is 4
implies slope of desired line is -1/4 (m1* m2 = -1)
so the eqn will be 
y+3 = -1/4(x-2)
4y + 12= 2-x
4y = -x - 10
y = -1/4(x +10)

anonymous · Answer

or y = -1/4x -5/2

anonymous · Answer

Tell her why at least, Tapan.
If two lines are perpendicular, then their slopes will be the opposite reciprocal. Reciprocal means flip it, opposite means switch the sign.

anonymous · Answer

thanks you both so much. What about  the equation of the line which passes through (2, 1) and is perpendicular to x = –2 ? it doesnt ask for a certain form though..

anonymous · Answer

x = -2 has a slope equal to 90 degrees
so d slope of perp line will be = 0
that is parallel to x- axis
so eqn will be y=1