Answer: 
Step-by-step explanation:
We know that the general form of the exponential decay formula is
, where y is final amount remaining after t time, A is the original amount and r is the rate of decay
Now, the ratio of strontium-90 remaining, p , as a function of years, t , since the nuclear accident. 
Hence, the ratio of remaining since the nuclear accident is
Answer:
x= 60
Step-by-step explanation:
if y is the other missing side
y^2 = 64^2 + 48^2
y^2 = 4,096 + 2,304
y^2 = 6,400
100^2 = x^2 +y^2
x^2 = 10,000 - 6,400
x^2 = 3,600
x = 60
The value of x would be 8
First do distrubutive property
-(x+4)=-8
Multiply the parenthesis by the invisible -1 in the front
: -x-4=-8
Now add 4 to both sides
-x=-4
then divide -1 by both sides
x=4 is your answer
