Scalar multiplication of a matrix refers to the
multiplication of all the elements of the matrix by an ordinary number which is
called a scalar.
From the given options the statements which are true about
scalar multiplication of matrices are;
a)
You can
multiply a matrix of any size by a scalar.
b)
For any matrix A, 1 × A = A.
c)
Scalar multiplication is a shortcut for repeated
addition of the same matrix.
Angles ∠ACD and ∠CAB are congruent because they are alternate angles. Then the area of the triangle AOB will be 22.53 square cm.
<h3>What is the
area of the right-angle triangle?</h3>
The area of the right-angle triangle is given as
A = 1/2 x B x H
Where B is the base and H is the height of the right triangle.
We know that angles ∠ACD and ∠CAB are congruent because they are alternate angles.
α₁ = 40°
AO = OC = 7.8 cm
Then the area of the triangle will be
Area = 1/2 x 7.8 x 7.8 x tan40°
Area = 22.53 square cm
More about the area of the right-angle triangle link is given below.
brainly.com/question/16653962
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Answer:
The 99% confidence interval is between 62.36%(lower bound) and 89.64%(upper bound).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
A sample of 65 students from the freshmen class is used and a mean score of 76% correct is obtained.
This means that 
99% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

0.6236*100 = 62.36%
0.8964*100 = 89.64%
The 99% confidence interval is between 62.36%(lower bound) and 89.64%(upper bound).
P(x)=-15+7/4=-2
P(y)=12-4/4=2
P=(-2,2)
431.2 is the answer to your question