10+-x3= -50 - 8x

Question

I've tried so hard but dont know how to do :/

 

Answer 1

10 - x³ = -50 - 8x

 

 

We want to have one side of the equation equal to zero.  Subtract 10 and add x³ on both sides of the equation.

 

0 = x³ - 8x - 60

 

 

Next, we divide the right side of the equation by the factor (x - c), where c is the possible root of the equation: ±1 , ±2 , ±3 , ±4 , ±5 , ±6 , ±10 , ±12 , ±15 , ±20, ±30,  ±60

 

The quotient must be zero in order for (x - c) to be a factor.  If we perform the division, we will see that this equation is not factorable.

 

 

Next method:  Use a graphing calculator to find the values of x.

 

Press MATH, then press 0.   This will take you to the Equation Solver.  Type the equation that you see here into the calculator.  Press ENTER.  Guess any number and press ALPHA, then press ENTER.  You will see that you will obtain irrational values for x.