Answer:
$13.67
Step-by-step explanation:
Let's say that CD= c and DVDs= d. Four CDs and 4 DVDs cost $164, so the equation will be:
i. 4c + 4d= 164
The cost of the 4 CDs is half the cost of the 4 DVDs, to put into an equation it will be:
ii. 4c= 0.5(4d)
4c= 2d
d= 2c
Then we can substitute the second equation (ii) into the first equation (i). The calculation will be:
4c + 4d= 164
4c + 4(2c)= 164
4c+ 8c= 164
12c= 164
c=13.67
The cost for each CD is $13.67
Answer: B and D
Step-by-step explanation:
I see you picked the first one which is close but not right. This isn't right because you are adding the area of both rectangles together and in the first choice the + 7 should be 7y because y is the height which is why the 4th choice is correct and the second choice if you distribute you get 5y + 7y which is the same so that would be right as well.
Answer: Susan’s favorite food is not pizza.
Step-by-step explanation: a counterexample is an example that shows the statement is false. So if most of the 9th graders in your school do not like pizza, then pizza would not be their favorite food.
The area of the parallelogram spanned by the given vectors is equal to the magnitude of their cross product.
(i + j + k) × (-2i + 3j + k)
= -2 (i × i) - 2 (j × i) - 2 (k × i)
… + 3 (i × j) + 3 (j × j) + 3 (k × j)
… + (i × k) + (j × k) + (k × k)
= - 2 (j × i) - 2 (k × i) + 3 (i × j) + 3 (k × j) + (i × k) + (j × k)
= 2 (i × j) - 2 (k × i) + 3 (i × j) - 3 (j × k) - (k × i) + (j × k)
= 5 (i × j) - 3 (k × i) - 2 (j × k)
= 5 k - 3 j - 2 i
Then the area of the parallelogram is
||-2 i - 3 j + 5 k|| = √((-2)² + (-3)² + 5²) = √38
