ALGEBRA 1B

Compute the value of x if x³ - 25 = 103 - x³.

Solution

x³ - 25 = 103 - x³.

x³ + x³ - 25 = 103

2x³ - 25 = 103

2x³ = 103 + 25

2x³ = 128

2x³ = 128⁶⁴

2        2

x³ = 64

x= 4  [since the cube root of 64 is 4]

Hence x=4

TRY THIS……………………… 

Compute the value of x if 2x³ - 101 = 74 - x³.
Answer: x=5.