# Finding Equations of a line

• Apr 26th 2009, 03:35 PM
Lespaul1216
Finding Equations of a line
19)find the equation of a straight line passing through (0,-3) & (-4,-11)

20)find the equation of the straight line passing through the point (-6,-4) and parallel to the line 2x+3y-15=0.

21)find the equation of a straight line passing through the point (-3,3) and perpendicular to the line 5x+2y+21=0

22.the lines -6x+2y=1 and x+3y-5=0 are

a.parallel to eachother
b.perpendicular to eachother
c.parallel to the line -x-3y=0
d.perpendicular to the line 3x-2y-1=0
e.neither parallel nor perpendicular to eachother

thank you for helping me, this is part of my study guide for my final
• Apr 26th 2009, 03:45 PM
stapel
19) Plug the two points into the slope formula. What do you get?

Plug either of the points, along with the slope you just found, into the point-slope form. What do you get?

Solve for "y=" to get the slope-intercept form. What do you get?

20) Solve the given line equation for "y=" and read off the slope value. What do you get?

Using what you know about slopes of parallel lines, what slope value do you get for the line equation you need to find?

Plug this slope value and the given point into the point-slope form, and solve for "y=" to get the slope-intercept form. What do you get?

21) This one works just like (20), except that the lines are perpendicular. Use what you know about the slopes of perpendicular lines to find the slope of the line you need to find. Then proceed as above.

What do you get?

22) Solve each equation for "y=", and read off the slope values. What do you get? What do you conclude?

Please be complete. Thank you! :D