What is the first step to take to solve the radical equation 12+x4−10−−−−−−√=8

To solve the radical equation \( 12 + \sqrt{x^4 - 10} = 8 \), the first step is to isolate the square root term.

So, you should subtract 12 from both sides of the equation.

This will simplify the equation to: \[ \sqrt{x^4 - 10} = 8 - 12 \] \[ \sqrt{x^4 - 10} = -4 \]

Since the square root of a number cannot equal a negative number, we can conclude that the original equation has no solution at this point.

However, following your prompt for the first step, the correct choice is: Subtract 12 from both sides of the equation.