Step-by-step explanation:
look it is very easy.
use formula of simple interest
In the equation of a straight line (when the equation is written as "y = mx + b"), the slope is the number "m" that is multiplied on the x, and "b" is the y-intercept (that is, the point where the line crosses the vertical y-axis)
Y=-1/20(x+3)^2
Your could always tell by which way the curve is pointing and if pointing down it’s a negative it’s pointing up it’s a positive
Hope that helped