Answer:
point D: (2, -4)
Step-by-step explanation:
 
        
             
        
        
        
Using it's concept, it is found that the sample mean package weight for Thursday is of 19 ounces.
<h3>What is the mean of a data-set?</h3>
The mean of a data-set is given by the <u>sum of the observations divided by the number of observations</u>.
For Thursday, the package weights in ounces are given by: {18, 19, 20, 19}.
Hence, the sample mean in ounces is of:
M = (18 + 19 + 20 + 19)/4 = 19.
More can be learned about the mean concept at brainly.com/question/24628525
 
        
             
        
        
        
This is an isosceles triangle. The definition of an isosceles triangle is a triangle with at least two congruent sides and angles. If 2 angles on a triangle are congruent (in this case 45 and 45 are two congruent angles) then triangle is isosceles. Therefore the two sides of triangle will be congruent. We know that the triangle is a right triangle because it has a hypotenuse. If a triangle has a hypotenuse then it's a right triangle. We can apply the Pythagorean theorem: a^2 + b^2 = c^2
A and B are the legs and C is the hypotenuse. 
We can plug C in the equation:
a^2 + b^2 = 128
What do we know about the legs of the isosceles triangle? They are congruent so a and b have to be equal. From here it's simply guess and check. Will 8 work?
8^2 + 8^2 = 128
64 + 64 = 128
128=128
Yes the value 8 works so the length of two legs of the triangle is 8.
        
                    
             
        
        
        
9 and 1/3 because you add what she has and what she's given and subtract what she uses. You must use a common denominator. Hope this helped you!