1. x=5
Explanation:
2(2x-3)=x+9
4x-6=x+9
-x -x
3x=15
x=5
2. x=-9
Explanation:
2(x+19)=x+29
2x+38=x+29
-2x -2x
9=-x
-9=x
10 x 7 = 70
1 x 7 = 7
9 x 7 = 70 - 7
9 x 7 = 63
If you are going to use mental math, round $0.98 up to $1.
Rounded, the cost of the 30 songs is $30.
However, since you rounded at the beginning, you need to subtract 2 cents for every song you purchased from the total of $30.
Multiply 30 by $0.02 to get $0.60. Subtract $0.60 from $30.
Your answer should be $29.40.