Answer:
It's the law of cosines
Step-by-step explanation:
law of cosines states that 
so we know that a = 7, b = 4, and alpha would be 135 degrees, so just plugging it in gets us 49+16-2*7*4*(-0.707) = 65 + 39.59 = 104.59
A millennium is 1000 years.
Multiply the number of seconds in 1 year by 1000:
31,536,000 x 1,000 = 31,536,000,000 seconds.
14t^3*6t
= (14*6)*(t^3*t)
= (2*7*2*3)*(t*t*t*t)
= 2*2*3*7*t*t*t*t
P(A|B)<span>P(A intersect B) = 0.2 = P( B intersect A)
</span>A) P(A intersect B) = <span>P(A|B)*P(B)
Replacing the known vallues:
0.2=</span><span>P(A|B)*0.5
Solving for </span><span>P(A|B):
0.2/0.5=</span><span>P(A|B)*0.5/0.5
0.4=</span><span>P(A|B)
</span><span>P(A|B)=0.4
</span>
B) P(B intersect A) = P(B|A)*P(A)
Replacing the known vallues:
0.2=P(B|A)*0.6
Solving for P(B|A):
0.2/0.6=P(B|A)*0.6/0.6
2/6=P(B|A)
1/3=P(B|A)
P(B|A)=1/3
There seems to be a typo. You wrote 1313, but I'm assuming you meant to say the fraction 1/3. If this assumption is correct, then continue with the rest of the solution. If the assumption is not correct, then ignore what I wrote below and please provide clarification of what the "1313" should represent. Thank you.
----------------
B = your brother's age
S = your sister's age
Y = your age
All of these ages are current present day ages.
---------------
"your brother is 1/3 your age" so B = (1/3)Y or B = Y/3.
"Your sister is 6 years older than your brother" so S = B+6
"Your sister is 10 years old" so S = 10.
---------------
S = B+6
B+6 = S
B+6 = 10 ... plug in S = 10
B+6-6 = 10-6 ... subtract 6 from both sides
B = 4
Your brother is 4 years old.
---------------
B = Y/3
Y/3 = B
Y/3 = 4 .... plug in B = 4
3(Y/3) = 3*4 ... multiply both sides by 3
Y = 12
<h3>Answer: Your age is 12 years old.</h3>
note: This answer hinges on assumption that the "1313" should be "1/3".