D. No because two points with the same x value have different y values. A function cannot have one x equal different y
Well, their speeds are (
is Jack's speed, and
is Richard's.
They, together, can paint 12 houses in 35 days. To get a single house, we only have to calculate
which is very close to 3 (a bit below)
2 3/8 / 1 1/4
= 19/8 / 5/4
=19/8 * 4/5
= 19/10
answer is B 19/10