-12 I just did this question In class
Answer: the original cost of the item is 90$
Step-by-step explanation:
30% off of the item = 27$
27 dollar is 30% of the item
thus 27 = 0.30X
0.30X = 27
time both side by 10
3X = 270
270/3 = 90
Answer:
x=-4
Step-by-step explanation:
(x+4) ^ (1/3) + (2x+8) ^ (1/3) = 0
Subtract (x+4) ^ (1/3) from each side
(x+4) ^ (1/3) - (x+4) ^ (1/3)+ (2x+8) ^ (1/3) = -(x+4) ^ (1/3)
(2x+8) ^ (1/3) = -(x+4) ^ (1/3)
Cube each side
(2x+8) ^ (1/3) ^3= -(x+4) ^ (1/3)^3
2x+8 = -(x+4)
Distribute the negative sign
2x+8 = -x -4
Add x to each side
2x+8 +x =-x+x-4
3x+8 = -4
Subtract 8 from each side
3x+8-8 =-4-8
3x =-12
Divide by 3
3x/3 = -12/3
x = -4
