Answer:
The equation can be used to determine the amount of money S(t) that her savings account has after t years is 
Step-by-step explanation:
A student invests $500 in a savings account
Principal = $500
Rate of interest = 4% = 0.04
We are supposed to find equation can be used to determine the amount of money S(t) that her savings account has after t years
Formula : 
Where A is the amount after t years =S(t)
t = time
r = rate of interest in decimals =0.04
P = Principal=500
Substitute the value in the formula :
So, 

Hence The equation can be used to determine the amount of money S(t) that her savings account has after t years is 
Answer:
I cant see the picture can you re post
Step-by-step explanation:
Yes. In fact
is a Pythagorean triple or simply right triangle where all sides are in
.
Hope this helps.
Answer:
The answer is the first graph.
Step-by-step explanation:
I did it on edge. I got it wrong the first time because I used an answer from this question. Because of that, I reported it. Now I have the correct answer lol.
X = 1 hr lessons and y = 1/2 hr lessons
x + y = 35......y = 35 - x
40x + 25y = 1115
40x + 25(35 - x) = 1115
40x + 875 - 25x = 1115
40x - 25x = 1115 - 875
15x = 240
x = 240/15
x = 16 <=== there are 16 one-hr lessons
and 19 half-hr lessons