60 blocks in 30 min
18 blocks in 9 min
Method 1
60-18 = 42
42 blocks in 21 min
Method 2
30-9 =21 min
Because it’s perpendicular, the slope must be -1/2, which is the opposite of 2. You can put the points into y-3=-1/2(x-4) and simplify if need be.
X = 12y - 20
y = 12y
Y is obviously greater than 20 when you multiply it by 12, so that's a hint.
x = 42
y = 22
3.5 • 12 + 22 = 64
I hope this helped you!
This might be wrong, but I think it's 15. Again, sorry if I'm wrong.