Slope of a line passing through two given points
= (y2-y1)/(x2-x1)
For m=3, and substituting coordinates,
3=(1-y)/(4-1)
solve for y
1-y=3*3=9
y=1-9=-8
Answer: y=-8
Zach has 399 marbles because 21*19 is equal to 399.
Here you go 3x-5.... hope this is what you looking for.
