25%=0.25
24*0.25=6
24-6=18
18 pairs are not black
It’s 3.5
use formula the formula
V=lwh
——
3


for example, let's look at the first set
y+3x =5 or y = -3x+ 5
and y = -3x + 2
y = m + b
the slopes are equal, the y-intercepts differ
that means, they're just parallel lines, no solution