Add numbers with the same amount of variables
-x^2 + (-7x^2) = -8x^2
– 28x (+ 14x )= -14x
7 (+ 8) = 15
-18x² - 14x + 15 is your answer
hope this helps
Answer:
8/27
Step-by-step explanation:
I only did the first part but maybe later I will solve the rest too. If there are any errors but tell me so I can update the pic.
9514 1404 393
Answer:
6.2
Step-by-step explanation:
We presume your "k-value" is the k in the exponential decay term ...
e^(-kt) . . . where t is the number of time units
This is 1/2 when ...
ln(1/2) = -kt
t = ln(1/2)/(-k) = ln(2)/k
t = 0.69315/0.1124 ≈ 6.2
The half life is about 6.2 time units.
