Hi, I think all of the above might work. In case what you need is simple, I used:
<body>
<div class="radio-buttons-choice" id="container-3-radio-buttons-choice">
<input type="radio" name="one" id="one-variable-equations" onclick="checkRadio(name)"><label>Only one</label><br>
<input type="radio" name="multiple" id="multiple-variable-equations" onclick="checkRadio(name)"><label>I have multiple</label>
</div>
<script>
function checkRadio(name) {
if(name == "one"){
console.log("Choice: ", name);
document.getElementById("one-variable-equations").checked = true;
document.getElementById("multiple-variable-equations").checked = false;
} else if (name == "multiple"){
console.log("Choice: ", name);
document.getElementById("multiple-variable-equations").checked = true;
document.getElementById("one-variable-equations").checked = false;
}
}
</script>
</body>