an attribute value specification must be an attribute value literal unless SHORTTAG Y

Line 22, Column 46: an attribute value specification must be an attribute value literal unless SHORTTAG YES is specified
<img src = "image/wave.jpg" alt ="" height = 100px width = 970px/>


Line 22, Column 60: an attribute value specification must be an attribute value literal unless SHORTTAG YES is specified
<img src = "image/wave.jpg" alt ="" height = 100px width = 970px/>

ok first of all, im new to XHTML, so probably im not sure what's going on here.

I have come across this error when i have checked with the w3c validator

the first error had the "1" highlighted in "..alt = "" height = 100px w.. "
and the next one the "9" was highlighted in "..width = 970px/>"

What does this mean and how to solve this problem?

Enclosed the height and width values in double quotes.

<img src="image/wave.jpg" alt="" height="100px" width="970px" />