Alright, so you have the basic formula- good.
You have the A value (400), the interest rate r (7.5% -> .075 in decimal), and the final P value (8500). So, we only need to solve for t.
8500 = (400)(1+.075)^t
/400 /400
21.25 = 1.075^t
logarithms are the inverse of exponents, basically, if you have an example like
y = b^x, then a logarithm inverts it, logy(baseb)=x
Makes sense if you consider a power of ten.
1000 = 10^3
if you put logbase10(1000), you'll get 3.
Anyways, though, to solve the problem make a log with a base of 1.075 in your calculator
log21.25(base 1.075) = t
also, because of rules of change of base (might want to look this up to clarify), you can write this as log(21.25)/log(1.075) = t
Thus, t is 42.26118551.
Rounded to hundredths, t=42.26
Answer:
-48
Step-by-step explanation:
i think im sorry if im wrong
Step-by-step explanation:
You have to substitute... 0, 5, & 10, & 3
y = 2x + 3
y = 2(0) + 3
y = 0 + 3
y = 3
(0,3)
y = 2x + 3
y = 2(5) + 3
y = 10 + 3
y = 13
(5,13)
y = 2x + 3
y = 2(10) + 3
y = 20 + 3
y = 23
(10,23)
y = 2x + 3
y = 2(3) + 3
y = 6 + 3
y = 9
(3,9)
The answer for your problem is shown on the picture.
If 0, and -8 are the roots of the quadratic equation we can write
(x-0)(x+8)=0
x(x+8)=0
x²-8x=0