<svg xmlns="http://www.w3.org/2000/svg" width="200" height="200">
    <rect x="10" y="10" width="180" height="180" fill="green"/>
    <rect transform="translate(200, 0)" x="10" y="10" width="180" height="180" fill="green"/>
    <script>
        function changeSize() {
            var svg = document.getElementsByTagName("svg")[0];
            svg.setAttribute("width", "400");
        }
    </script>
</svg>