Answer:
X = -5
Step-by-step explanation:
-6x + 18 = 7 - (4x + 9)
first we simplify the parentheses.
distribute the invisible number one created by the negative sign in front of the parentheses to get -6x + 18 = 7 - 4x - 9
then simplify further by subtracting 9 from the right side, leaving you with
-6x + 18 = -2 - 4x
next, add 2 to both sides to isolate the variable.
-6x + 20 = -4x
then, to isolate the variable further add 6x to both sides.
20 = -4x
divide both sides by -4 to isolate the variable
-5 = x
so, x = -5
Answer:
(a) 
and 
are indeed mutually-exclusive.
(b) 
, whereas 
.
(c) 
.
(d) 
, whereas 
Step-by-step explanation:
<h3>(a)</h3>
means that it is impossible for events and to happen at the same time. Therefore, event and are mutually-exclusive.
<h3>(b)</h3>
By the definition of conditional probability:
.
Rearrange to obtain:
.
Similarly:
.
<h3>(c)</h3>
Note that:
.
In other words, and are collectively-exhaustive. Since and are collectively-exhaustive and mutually-exclusive at the same time:
.
<h3>(d)</h3>
By Bayes' Theorem:
.
Similarly:
.
