√104+√40+√160=x√x

√104+√40+√160=x√x    write the right side in exponential form

2√26 + 2√10 + 4√10 = x^3/2       combine like terms

2√26 + 6√10 = x^3/2       exponentiate both sides to the 2/3rds  power

[(2√26 + 6√10)²]³ =  x  =  about 9.476