The missing angle is 49 :)
The question is incomplete, here is the complete question:
Recall that m(t) = m.(1/2)^t/h for radioactive decay, where h is the half-life. Suppose that a 500 g sample of phosphorus-32 decays to 356 g over 7 days. Calculate the half life of the sample.
<u>Answer:</u> The half life of the sample of phosphorus-32 is 
<u>Step-by-step explanation:</u>
The equation used to calculate the half life of the sample is given as:

where,
m(t) = amount of sample after time 't' = 356 g
= initial amount of the sample = 500 g
t = time period = 7 days
h = half life of the sample = ?
Putting values in above equation, we get:

Hence, the half life of the sample of phosphorus-32 is 
In mathematical notation, ∑ means summation. So wherever you see the symbol, you have to sum over all elements in the set. Let's solve the question.
a. ∑m means, to sum all elements in the set m: ∑m = 12 + 15 + 20 + 30 = 77
b. ∑
means to sum all elements in the set f as the square of the elements f = 
c. ∑mf means to sum all elements as the product of the elements of m and f = (12×5) + (15×9) + (20
10) + (30×16) = 875
d. ∑
means to sum all elements as the product of the square of m and f = 
Answer:
x=13
Step-by-step explanation:
Well, the triangle is always equal to 180 degrees in total. Lets remember that x will always be the same in every equation.
So, (5x-11) x (2x+20) x (11x-63) = 180.
Now, take away the parenthesis and add up all the like terms.
This should = 18x-54 = 180.
Now solve like you regularly would. Add 54 on both sides which equals,
18x=234. Now, divide 18 on both sides.
x = 13.
Hope this helps.
Given:
The graph of a line segment.
The line segment AB translated by the following rule:

To find:
The coordinates of the end points of the line segment A'B'.
Solution:
From the given figure, it is clear that the end points of the line segment AB are A(-2,-3) and B(4,-1).
We have,

Using this rule, we get


Similarly,


Therefore, the endpoint of the line segment A'B' are A'(2,-6) and B'(8,-4).