SOLUTION: Write the equation of a line through C that is parallel to AB? A(-1,4) B(3,1) C(0,-3) The equation is y= mx + b.

Algebra ->  Formulas -> SOLUTION: Write the equation of a line through C that is parallel to AB? A(-1,4) B(3,1) C(0,-3) The equation is y= mx + b.      Log On


   

Question 1110331: Write the equation of a line through C that is parallel to AB?
A(-1,4) B(3,1) C(0,-3)
The equation is y= mx + b.
Found 2 solutions by josgarithmetic, josmiceli:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Point C already shows the value for b.

Use Formula for slope, m, the find slope for the line of AB.

y=%28%284-1%29%2F%28-1-3%29%29x-3
Simplify this.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
A( -1, 4 )
B( 3, 1 )
Slope = [ change in y ] / [ change in x ]
+m+=+%28+4+-+1+%29+%2F+%28+-1+-+3+%29+
+m+=+3+%2F+%28-4%29+
+m+=+-3%2F4+
----------------------
+m+ is also the slope of any
line parallel to this on
-----------------------------
Use the general point-slope formula
C( 0, -3 )
+%28+y+-%28-3%29+%29+%2F+%28+x+-+0+%29+=+-3%2F4+
+%28+y+%2B+3+%29+%2F+x+=+-3%2F4+
Multiply both sides by +4x+
+4%2A%28+y+%2B+3+%29+=+-3%2Ax+
+y+%2B+3+=+%28-3%2F4%29%2Ax+
+y+=+%28-3%2F4%29%2Ax+-+3+