5 · 5 - 4 · 4 = 9 sorry if I'm wrong
the dots mean to multiply
Answer:
(27.3692 ; 44.6308)
Step-by-step explanation:
Mean, xbar = 36
Standard deviation, s = 11
Sample size, n = 12
Tcritical at 0.2, df = 12 - 1 = 11 ; Tcritical = 2.718
Confidence interval :
Xbar ± Margin of error
Margin of Error = Tcritical * s/sqrt(n)
Margin of Error = 2.718 * 11/sqrt(12) = 8.6308
Confidence interval :
Lower boundary : 36 - 8.6308 = 27.3692
Upper boundary : 36 + 8.6308 = 44.6308
(27.3692 ; 44.6308)
Answer:
It is necessary four parameters.
Step-by-step explanation:
Since the augmented matrix of the consistent system has rank equal to three then the number of free variables is (number of unknows)-rank then there are 7-3=4 free variables. This means that are necessary four parameter to specify all solutions.
<h2>
Answer:</h2>
<h2>
Step-by-step explanation:</h2>
For a better understanding of this problem, see the figure below. Our goal is to find 
. Since:
and is a common side both for ΔMRN and ΔMQN, then by SAS postulate, these two triangles are congruent and:
By Pythagorean theorem, for triangle NQP:
Applying Pythagorean theorem again, but for triangle MQN:
