NA_HW2_2

by ikatyang

JavaScript

function solve_1A(p1, q1, p2, q2) {
	var a = q2 - q1;
    var b = p1 - p2;
    var c = p2 * q1 - p1 * q2;
    return [a, b, c];
}
function solve_1B(a1, b1, c1, a2, b2, c2) {
    var d = a2 * b1 - a1 * b2;
    var x = (b2 * c1 - b1 * c2) / d;
    var y = -1 * (a2 * c1 - a1 * c2) / d;
    return [x, y];
}

// l1: (4, 9), (8, 17)
var l1 = solve_1A(4, 9, 8, 17);
console.log(l1);
// l1: 8x - 4y + 4 = 0

// l2: (1, 6), (-2, -6)
var l2 = solve_1A(1, 6, -2, -6);
console.log(l2);
// l2: -12x + 3y - 6 = 0

var p = solve_1B(l1[0], l1[1], l1[2], l2[0], l2[1], l2[2]);
console.log(p);
// p = (-0.5, 0)