It’s bevause you can see what you are doing instead of doing it all of your head which could get messed up.
Parallel have same slope
Perpendicular have opposite reciprocal slopes. Ex. 2/3 is slope of one line so the perpendicular line would have slope of -3/2.
Find slopes of these lines.
-4x-5y=-4
-4x+4 =5y
Divide by 5
Y= -4x/5 +4/5
Second line: 10x-8y=-1
10x+1=8y
Divide by 8
10x/8 +1/8 =y
Y= 5x/4 +1/8
So if you look at slope of line 1= -4/5 and line 2 it’s 5/4 so these both are perpendicular.
Answer:
C. Many ang sagot............
