Answer:
EF = 58/7
Step-by-step explanation:
If you extend both BC and AD to meet at P you get 3 similar triangles PAB, PEF, and PCD. Let's call BF = 3x and FC = 4x. Therefore the following proportions can be expressed:
BP/7 = (BP+7x)/10
10BP = 7*(BP+7x)
10BP = 7BP+49x
3BP = 49x
BP = (49/3)x
BP/7 = (BP+3x)/EF
EF = (BP+3x)*7/BP
EF = ((49/3)x + 3x)*7/((49/3)x)
EF = ((58/3)x*7*3)/(49x)
EF = 58/7
Answer:
<em>There will be left 80.4 of the sample in 500 years</em>
Step-by-step explanation:
<u>Radioactive Decay Model</u>
Suppose N is the size of a population of radioactive atoms at a given time t, No is the size of an initial population of radioactive atoms at time t = 0, and k is the decay constant, then the equation is as follows:
The time required for half of the original population of radioactive atoms to decay is called the half-life Th. The relationship between the half-life and the decay constant is:
We know the half-life of radium-226 is about 1,590 years. We can find the value of k by solving the above equation:
k=0.000436
The initial mass of the sample is 100 gr, thus the model for the mass at time t is:
When t=500 years:
M(500)=80.4 gr
There will be left 80.4 of the sample in 500 years
Answer:
extraneous is -9 and the true solution is -2
Step-by-step explanation:
Answer:
the place value of 4 is 4 × 1000 = 4000 as 4 is at thousand's place. (iv) Here, we also see that the place value of the digit 0 in a number is always zero, whatever may be its position.
Step-by-step explanation: