The way to solve this question is to essentially reverse the equation I used in the other answer.
I would solve this with some theoretical values. If you start with 3, how long would it take for it to triple, or reach 9.
the equation would look like 9 = 3(2)^t/6, note how the instead of 1/2 it is now 2 in the parenthesis, as it doubles every 6 hours rather than halves every amount of hours.
When placed into an algebra calculator, the answer should be about 9.5 hours
Answer:
x²-8x-1=0
comparing above equation with ax²+bx+c=0
a=1
b=-8
c=-1
x=
=(--8+-√(64-4×1×-1)/2×1
=8+-√(64+4)/2
taking positive
x=(8+√68)/2=2(4+√17)/2=4+√17
taking negative
x=(8-√68)/2=2(4-√17)/2=4-√17
Answer:
8-2 and 10-3
Step-by-step explanation:
Count change of signs to tell positive roots
then replace x with -x and evaluate, then count change in sign for negative roots
initially
+, -, -, +, +, -
3 changes
3 or 1 positive roots
replacing x with -x
-,-,+,+,-,-
2 changes
2 or 0 negative roots
B is answer
Answer:
Below.
Step-by-step explanation:
These are perpendicular line which intersect at (-4, -9).
Vertical line is x = -4.
Horizontal lone is y = -9.
