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.
Answer:Surface
Step-by-step explanation:
Answer:
the answer should be -1
Step-by-step explanation:
-3 + (-2) + (-4) = -9
-9 + 4 = -5
-5 ÷ 5 = -1
Hope this helped :)
Okay, these get easy with practice so don't post all of these online. First, substitute y in 3x-2y=9 for what it says y equals (2x-7). You now have: 3x-2(2x-7)=9. Breakdown:
3x-2(2x-7)=9
3x-4x+14=9
-1x=-5
x=5
next solve for y
y=2x-7
y=2(5)-7
y=10-7
y=3
And now we have x=5, and y=3.
Answer: 296
Step-by-step explanation: explicit rule formula for an arithmetic sequence:
a_n = a_1 +(n-1)(d)
20-14= 6
d= 6
a_1 = 8
a_n = 8 + (n-1)(6)
= 8+6n-6
a_n= 6n+2
substitute to find answer:
a_49= 6(49) +2
= 294+2
=296
