Teaser box images

I tried to create a specific teaser box image for the image part but it automatically enlarges it to about 200% so instead i thought i would use insert media and put the image aligned left into the text. It is still enlarging the image and centering it. How do i get the image to appear at 100% and left aligned- what code is directing the image sizing here? OR Alternatively can i set a specific image size and get it to appear at that size for the header image? i had sized the header image to the same size as the blog carousel image 360×102

see screenshot attached. tried to attach two images but it wont let me.

thanks!