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:
y=-3
Step-by-step explanation:
If the line is parallel to the x-axis then it is a horizontal line with slope 0. These lines have form y=b where b is the y-intercept or y value of all points. y=-3 is the line since (2,-3) is on the line.
The answer is 4x-8+4y i think?
A fraction x/y is a ratio between two numbers x and y.
The ratio is preserved if both x and y are scaled up or down by the same number n.
This means you can obtain any fraction equivalent to x/y by multiplying both x and y by n, i.e. (n*x)/(n*y).
Then we have 1/4 = (2*1)/(2*4) = 2/8, for example.
You can not use either of them because neither of them have a variable= to the eqaution
ex.) y= 3x+25
