You are subtracting 3 each time. (-3)
It is asking you to convert them to different units of measurements.
Answer:
x = 4/7
Step-by-step explanation:
x^3 = 64/ 343 // - 64/ 343
x^3 - ( 64/ 343 ) = 0
x^3 - 64 / 343 = 0
1*x^3 = 64/ 343 // : 1
x^3 = 64/ 343
x^3 = 64/ 343 // ^ 1/3
x = 4/ 7
x + 7 = 2(3x - 4) Remove the brackets
x + 7 = 2*3x - 4*2
x + 7 = 6x - 8 Subtract 7 from both sides.
x + 7 - 7 = 6x - 8 - 7
x = 6x - 15 Subtract 6x from both sides
x - 6x = - 15
-5x = - 15 Divide by -5
-5x/-5 = -15/-5
x = 3
9/10 or 0.9
Hope this helps