2x+y=9
3x+5y=19
I will do this problem in 2 ways. I.)Substitution II.)Elimination
Solution I.) Substitution
We can subtract 2x from both sides in the first equation.
y=9-2x
Now we can substitute the y in the second equation with 9-2x
3x+5(9-2x)=19
-7x+45=19
-7x=-26
x=26/7
y=9-2(26/7)=11/7
Solution II.)Elimination
We can multiply both side of first equation by 5 to get a 5y in both equations.
10x+5y=45
Now because both are positive 5y we just need to do simple subtraction of the 2 equation, each side respectively.
(10x+5y)-(3x+5y)=45-19
7x=26
x=26/7
2*26/7+y=9
y=11/7
Ultimately you get the same answer, both are viable methods, some problems are faster with one method but I recommend mastering both since they are very useful.
Theres only 4 but the answer is -15
Binomial probability states that the probability of x successes on n repeated trials in an experiment which has two possible outcomes can be obtained by
(nCx).(p^x)⋅((1−p)^(n−x))
Where success on an individual trial is represented by p.
In the given question, obtaining heads in a trial is the success whose probability is 1/2.
Probability of 6 heads with 6 trials = (6C6).((1/2)^6).((1/2)^(6–6))
= 1/(2^6)
= 1/64
The slope equals 1/2 (rise over run)
