Answer:
Where is the N in the equation
We know that
applying the law of cosines
a² = b²+ c²<span> – 2*b*c*cos(A)
cos (A)=[b</span>²+c²-a²]/[2*b*c]
in this problem
a=10
b=17
c=18
so
cos (A)=[17²+18²-10²]/[2*17*18]-----> cos (A)=0.8382
A=arc cos (0.8382)-----> A=33.05°-----> A=33°
the answer is
33 degrees
13 cm+ 13 cm= 26 cm, 26 cm is the answer to Part B.
Answer:
For this case the value of r = -0.66
Now we can calculate the determination coeffcient:

And then we can conclude that 43.56% of the variation in y can be explained by the explanatory variable
And then 100-43.56 = 56.44 % of the variation in y that cannot be explained by the explanatory variable
Step-by-step explanation:
For this case we need to calculate the slope with the following formula:
Where:
And we can find the intercept using this:
And the model obtained for this case is:

The correlation coefficient is a "statistical measure that calculates the strength of the relationship between the relative movements of two variables". It's denoted by r and its always between -1 and 1.
And in order to calculate the correlation coefficient we can use this formula:
For this case the value of r = -0.66
Now we can calculate the determination coeffcient:

And then we can conclude that 43.56% of the variation in y can be explained by the explanatory variable
And then 100-43.56 = 56.44 % of the variation in y that cannot be explained by the explanatory variable