curl --request POST \
  --url https://api.iotools.cloud/v1/tool/polynomial-roots-calculator \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "coefficients": "1, -5"
}
'

{
  "tool": "polynomial-roots-calculator",
  "tool_version": "1.0.2",
  "outputs": {
    "equation": "x - 5 = 0",
    "roots": [
      {
        "root": "5",
        "real-part": "5",
        "imaginary-part": "0"
      }
    ],
    "method": "Linear equation — solved directly: x = −b⁄a."
  },
  "credits_used": 5,
  "credits_remaining": null
}