What is the distance between the parallel lines having equations 2x+2y=16 and x+y=0
a) 16
b) 4 root 2
c) 2
d) 8
I got the answer 2. I solved for y in the 2x+2y=16 equation and got 8. that gave me point (0,8)
I used the d= (ax+by+c)/root (a^2+b^2) using the equation x+y=0 and got 2 as my answer
Yes, b is correct.
Your method works well without having to memorize formulas.
If the equations had been in the slope intercept form:
y=-x+8 and
y=-x
then you could also calculate using
distance = y-intercept difference / &radic(1²+(-1)²)
=8/√2
=4√2