Solve linear equation with three variables

SolveLinearEquationWithThreeVariables.cs

using System;
using System.Collections.Generic;

class ThreeVariableLinearEquation
{
    public float ACoefficient;
    public float BCoefficient;
    public float CCoefficient;
    public float Answer;

    public ThreeVariableLinearEquation(float a, float b, float c, float answer)
    {
        ACoefficient = a;
        BCoefficient = b;
        CCoefficient = c;
        Answer = answer;
    }
}

class Matrix3x3
{
    public float A {get; set;}
    public float B {get; set;}
    public float C {get; set;}
    public float D {get; set;}
    public float E {get; set;}
    public float F {get; set;}
    public float G {get; set;}
    public float H {get; set;}
    public float I {get; set;}
    
    public Matrix3x3
    (
        float a,
        float b,
        float c,
        float d,
        float e,
        float f,
        float g,
        float h,
        float i
    )
    {
        A = a;
        B = b;
        C = c;
        D = d;
        E = e;
        F = f;
        G = g;
        H = h;
        I = i;
    }

    public float CalculateMatrix()
    {
        return A * E * I +
            B * F * G +
            C * D * H -
            C * E * G -
            B * D * I -
            A * F * H;
    }
}

class MainClass
{
    private static List<float> SolveThreeVariableLinearEquation(ThreeVariableLinearEquation A, ThreeVariableLinearEquation B, ThreeVariableLinearEquation C)
    {
        float delta = new Matrix3x3
        (
            A.ACoefficient, A.BCoefficient, A.CCoefficient,
            B.ACoefficient, B.BCoefficient, B.CCoefficient,
            C.ACoefficient, C.BCoefficient, C.CCoefficient
        ).CalculateMatrix();
        float deltaX = new Matrix3x3
        (
            A.Answer, A.BCoefficient, A.CCoefficient,
            B.Answer, B.BCoefficient, B.CCoefficient,
            C.Answer, C.BCoefficient, C.CCoefficient
        ).CalculateMatrix();
        float deltaY = new Matrix3x3
        (
            A.ACoefficient, A.Answer, A.CCoefficient,
            B.ACoefficient, B.Answer, B.CCoefficient,
            C.ACoefficient, C.Answer, C.CCoefficient
        ).CalculateMatrix();
        float deltaZ = new Matrix3x3
        (
            A.ACoefficient, A.BCoefficient, A.Answer,
            B.ACoefficient, B.BCoefficient, B.Answer,
            C.ACoefficient, C.BCoefficient, C.Answer
        ).CalculateMatrix();
        List<float> result = new List<float>();
        result.Add(deltaX / delta);
        result.Add(deltaY / delta);
        result.Add(deltaZ / delta);
        return result;
    }
    
    public static void Main (string[] args)
    {
        ThreeVariableLinearEquation A = new ThreeVariableLinearEquation(8, 1, -7, 15);
        ThreeVariableLinearEquation B = new ThreeVariableLinearEquation(8, 0, 3, 30);
        ThreeVariableLinearEquation C = new ThreeVariableLinearEquation(4, 3, 0, 27);
        List<float> abc = SolveThreeVariableLinearEquation(A, B ,C);
        Console.WriteLine($"{abc[0]}, {abc[1]}, {abc[2]}");
    }
}