Trying to miscalculate math

So, there is an inside joke in my server where someone said 9 + 2 = 12, so I'm coding my bot so when someone says, "cal 9 + 2", the bot shows an embed which says calculator as title, and a answer of 12, which works well, but any other calculations wont work, here is the code:

const Math = require("mathjs");

module.exports = {
    name: "cal",
    description: "Calculates something",

    async execute (Client, message, args, Discord){
        const lol = '12'
        const LOL = '9 + 2'

        if(!args[0]) return message.channel.send("Please provide a question to solve");

        let resp;

        try{
            resp = Math.evaluate(args.join(" "))
        } catch (e) {
            return message.channel.send("Please provide a **valid** question to answer")
        }
        if(args[0] = '9+2' || '9 + 2' || '9+ 2' || '9 +2'){
            const embed = new Discord.MessageEmbed()
            .setColor("RANDOM")
            .setTitle("Calculator")
            .addField("Question", `\`\`\`css\n${LOL}\`\`\``)
            .addField("Answer", `\`\`\`css\n${lol}\`\`\``)

            message.channel.send(embed);
        }
        else{
            const embed = new Discord.MessageEmbed()
            .setColor("RANDOM")
            .setTitle("Calculator")
            .addField("Question", `\`\`\`css\n${args.join(" ")}\`\`\``)
            .addField("Answer", `\`\`\`css\n${resp}\`\`\``)

            message.channel.send(embed);
        }
    }
}

the script without the if function, the math part works perfectly! but the joke aint there.

Your problem is with this line:

if(args[0] = '9+2' || '9 + 2' || '9+ 2' || '9 +2'){

First of all, = is used only for assignments, such as const foo = 'bar'. For comparison, use the triple equals, such as 'foo' === 'foo'.

Second of all, x === y || z does not actually do what you think it does. Statements on both sides of the logical OR operator (||) will always be evaluated completely separately. The above will not mean, "x equals either y or z" but instead, "x equals y, or z is truthy"

// this means that something like this
// will always return truthy.
// if you separate the two statements, 
// the second will always be truthy because
// a string, by itself, *is* truthy

if (true === false || 'hello') {
  console.log('It passed');
};

Instead of x === y || z, you'll have to take the more verbose option, which is:

x === y || x === z /* ... */

Or, you could use Array#includes(), and put all of the valid strings in an array:

// x === y || x === z
[y, z].includes(x);

For your situation, however, I think the best option would be to use RegExp#test(), with a regex such as: ^9\s*\+\s*2$:

if (/^9\s*\+\s*2$/.test(message.content)) {
  // ...
}