Request Class Manipulation

$myvar = $feet . " -  "  . $inchs;

Something like that.

I apologize what would I do in my form request class to replace it. I have the Eloquent model creation in my controller and want to keep it from having to do the calculation in there and then do it in the form request class and then replace in the form request class as well.

User::create([
    'height' => (request('feet', 0) * 12) + request('inches', 0),
]);

<?php

namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;
use Illuminate\Validation\Rule;

class UserFormRequest extends FormRequest
{
    /**
     * Determine if the user is authorized to make this request.
     *
     * @return bool
     */
    public function authorize()
    {
        return true;
    }

    /**
     * Get the validation rules that apply to the request.
     *
     * @return array
     */
    public function rules()
    {
        return [
            'feet' => 'required|integer',
            'inches' => 'required|integer|max:11',
        ];
    }
}