I think you could try adding up all the x and then divided
Answer:

Step-by-step explanation:
we are given half-life of PO-210 and the initial mass
we want to figure out the remaining mass <u>after</u><u> </u><u>4</u><u>2</u><u>0</u><u> </u><u>days</u><u> </u>
in order to solve so we can consider the half-life formula given by

where:
- f(t) is the remaining quantity of a substance after time t has elapsed.
- a is the initial quantity of this substance.
- T is the half-life
since it halves every 140 days our T is 140 and t is 420. as the initial mass of the sample is 5 our a is 5
thus substitute:

reduce fraction:

By using calculator we acquire:

hence, the remaining sample after 420 days is 0.625 kg
Answer:
Lines A and B form a consistent independent system
Step-by-step explanation:
we know that
A consistent system of equations has at least one solution
In this problem
The system of Line A and Line B has only one solution, since it has only one point of intersection.
and the Line A is different to Line B
therefore
Lines A and B form a consistent independent system
(independent because Lines A and B are different)
Answer:
5/3
Step-by-step explanation:
The opposite of a number always has to have the same distance from zero, positive or negative. So in this case, since -5/3 is a negative fraction, the answer would be 5/3. This fraction may be positive but they have the same distance from zero.