Remember, you can do anything to an equation as long as you do it to both sides
and when multiply or divide by a negative in inequalities, flip the direction of the sign
12x-39<9
add 39 to both sides
12x<48
divde bothh sides by 12
x<4
-4x+3<-6
minus 3 both sides
-4x<-9
times both sides by -1 and flip sign
4x>9
divide both sides by 4
x>9/4
Answer:
Let Craigs age = x
Therefore Dianes age = 25 + x ( since she's 25 years older)
Dianes + Craigs age = (25 + x) + x = 105 (They said both of their ages sums up to 105)
25 + 2x = 105
2x = 80
x = 40
Craigs age is 40 years old.
Dianes age is 65 years old.
SOLUTION:
Case: Percentages
Method:
The sale price after 30% off is $6800
Let the original price be 'x'
30% off means 70% of the original price

Final answer: (Nearest cents)
The original price was $9714.29