I’m not 100% sure but isn’t it x2 +xy +y2?
I = PRT...and since we are looking for r.....I / PT = R
I / PT = R
I = 510
P = 3000
T = 4
510 / (3000 * 4) =
510 / 12,000 =
0.0425 .....multiply by 100 to get the percent
4.25% <==
D ~ Positive Exponetial growth. Hope it helped!!! <3 (^u^)
I need more information to figure out what you need