This is simple interest : $640, 3%, 2 years anyone knows how to explain?

I=PRT
Interest=I
P=principal
R=rate in decimal
T=time in years

given
asuming 640 is the principal and not the interest
P=640
R=3%=0.03
T=2

I=640*0.03*2
I=19.2*2
I=38.4

interst=$38.40

movement

Explanation:

movement is important because with movement we learn and get new ideas from around the world

x=236

Step-by-step explanation:

44+80+x=360

x=solve it

First you want to reduce the brackets
Next you want to factor out the common number 3
Next you want to factor 20 + x^3 + 11x - 8x^2 by using the polynomial division method/technique 
Lastly you just factor x^2 - 9x + 20 to get the answer.

Yes you are correct, the solutions are 1, 4, and 5.

If it is I parenthesis then u multiply so here is an example f=4 x=1 then u could say 4×1=? and 3×4=? this is not an real answer it is just an example