Answer:
b and c
Step-by-step explanation:
Answer/Step-by-step Explanation:
Given:
a = no. of DVDs
b = no. of CDs
Total cost ($) for DVDs and CDs = 
a. The cost for 1 DVD = 2.5(a) = 2.5(1) = $2.5
The cost for 1 CD = 2(b) = 2(1) = $2
b. Total cost for 4 DVDs and 4 CDs:
Substitute a = 4, and b = 4 into the equation.


Total cost for 4 DVDs and 4 CDs = $18
c. To find out if $20 would be enough to buy 6 DVDs and 3 CDs, substitute a = 6, and b = 3 into the equation. Solve for the total cost to see if it equals $20 or is less than $20. If it's greater than $20, then it won't be enough.


6 DVDs and 3 CDs cost more than $20, therefore, $20 is not enough.
9514 1404 393
Answer:
A- Cai are used an invalid reason to justify the congruence of a pair of sides or angles.
Step-by-step explanation:
In step 4, Cai referred to the angles as "alternate interior." In fact, they are "corresponding." The reason used to justify congruence of the angles was invalid.
Answer:
4/9 are boys
Step-by-step explanation: