Step 1 : Simplify both sides
-5(6a+21)=-15
(-5)(6a)+(-5)(21)=-15
-30a-105=-15
Step 2 : Add 105 to both sides
-30a-105+105=-15+105
-30a=90
Step 3 : Divide both sides by -30
-30a=90
—————
-30 -30
a = -3
Rileyflipflop,

= 8

, since she can't buy half a CD, she's limited to no more than 8 CDs. If x = the cost of one CD, then x CDs cost $18x. Since we are limited to $153, our equation looks like... 18x < 153x < 8

Again, since we can't buy half a CD, your answer should actually be... x ≤ 8 since we can buy 8 CDs or fewer.
Answer:
(a) 9
Step-by-step explanation:

substitute r = 4, t = 2

simplify

cubic of 2 is 8

simplify

Answer: combine
Step-by-step explanation:
When you combine like terms, it shortens or simplified the equation
Example: 2x-5+15
Combine actual numbers -5 and 15.
2x+10