change rises 4 feet in 9 seconds into an equation with two variables and change moves 900 ft every 10 seconds into an equation with two variables
y = (4/9) x
y = (900/10) x or y = 90x
y = mx + b
where m = slope = change in y divided by the change in x.
Time would always be on the x axis.
Can you put this into 6th-grade terms, please?
Y (or height) = 4/9 t (for time)
y = 90x