Answer:
3
Step-by-step explanation:
2y - 6y = 5 - 17
-4y = -12
y = 3
Answer:
Step-by-step explanation:
There are 11 students in total.
6 girls.
and 5 boys.
so the probability of selecting a girl is 1/5 because 5 boys or it could be 1/11 if i am not mistaken.
(which i might be)
5+23= 28 .........................
9514 1404 393
Answer:
- as written: none
- perhaps intended: 0
Step-by-step explanation:
The expression written here is interpreted according to the Order of Operations as ...
8x -(5/6)x
This reduces to (7 1/6)x, which is defined for all real numbers.
__
Maybe you intended the expression ...
(8x -5)/(6x)
This expression is undefined where its denominator is zero, at x = 0.
Use the double angle identity:
sin(2<em>x</em>) = 2 sin(<em>x</em>) cos(<em>x</em>)
Now rewrite
sin(2<em>x</em>) sin(<em>x</em>) + cos(<em>x</em>) = 0
as
2 sin²(<em>x</em>) cos(<em>x</em>) + cos(<em>x</em>) = 0
Factor out cos(<em>x</em>) :
cos(<em>x</em>) (2 sin²(<em>x</em>) + 1) = 0
Consider the two cases,
cos(<em>x</em>) = 0 OR 2 sin²(<em>x</em>) + 1 = 0
Solve for cos(<em>x</em>) and sin²(<em>x</em>) :
cos(<em>x</em>) = 0 OR sin²(<em>x</em>) = -1/2
Squaring a real number always gives a non-negative number, so the second case doesn't offer any real solutions. We're left with
cos(<em>x</em>) = 0
Cosine is zero for odd multiples of <em>π</em>/2, so we have
<em>x</em> = (2<em>n</em> + 1) <em>π</em>/2
where <em>n</em> is any integer.