Some Notes about Highcharts
I have tried two JS libraries for drawing graphics using HTML SVG - C3.js and Highcharts - but compared to the two, I personally feel that C3 is more difficult to use and requires a lot of parameters: the advantage is that I can control a lot of things myself, but the disadvantage is that development is very slow and annoying (that's why there is a D3.js to take over the market). Recently, I used Highcharts, and I feel pretty good. Its documentation and examples are relatively fresh, and the parameters for drawing are quite simple (well, but the parameters are not necessarily much less), which is much more comfortable than C3.js. It's even better when you work together with CoffeeScript.
Documentation is here: http://api.highcharts.com/highcharts
This demo is also good: http://www.highcharts.com/demo/combo-dual-axes
An example for online debugging: http://jsfiddle.net/1xwdmnsn/