Answer:
y = 1.5x+4.5
Explanation:
Let's try to fit this into slope-intercept form, which is y=mx+b, where m=slope and b=y-intercept.
Rate of change means slope, so m=3/2 = 1.5.
y = 3/2x+b
We can plug in the given point, remembering that it's in the form (x,y), so x=4, y=10.5.
y = 3/2x+b
10.5 = 3/2*4 + b
4.5 = b
Plug b back in.
y = 1.5x+4.5