Write an equation in point-slope form of the line through point J(4, –4) with slope 4.

Question

amorfide · Answer

standard equation of a line is
y=mx+b
where b is the y intercept, and m is the slope
we know that the slope is 4
so m=4

y=4x+b

standard coordinate is (x,y)
we know the point (4,-4)
so x=4, y=-4

substitute these values into y=4x+b
and work out b

mathmale · Answer

This approach will certainly work!  However, it'd be faster to begin with the general "point-slope form of the equation of a straight line and then substitute the given slope and point coordinates.

$$y-y _{1}=m(x-x _{1})$$

tkhunny · Answer

Point-Slope: $(y-y_{0}) = m(x-x_{0})$

You are given the point, $(x_{0},y_{0})$
You are given the slope.

Substitute the three values.

mathmale · Answer

Please begin that substitution now, and share your work.

mathmale · Answer

Would you please not just post a question and then log off.  To be fair, stick around for a few minutes at least to see whether anyone tries to help you.

sshayer · Answer

eq. of a line is y=mx+b  ...(1)
if it passes through (x1,y1)
y1=m x1+b   ....(2)
subtract (2) from (1)
y-y1=m(x-x1)