Parallel and perpendicular lines

Question

Question no. 1 Determine a line that passes through (5,-2) and perpendicular to 4x+y=2

 

 

Question no. 2 What is the equation of a line with y-intercept-5 and parallel to SF from points S(-1,3) and F (3,0)?

 

 

Thank you

Answer 1

Q2.  first, calculate the slope of line SF;you have two points, so just use the m formula.  any line // to that will use the same slope, so you can write the equation y = mx + b using the m just obtained and b = -5

 

Q1. begin by observing that the line 4x+y=2 has slope -4; any perpendicular thereto will have slope-¼ (neg. reciprocal of other slope).  so now you have YOUR m = -¼ and you can use Point Slope form to write the equation based on (5,-2) being on your line.