To find these two lets convert this into slope-intercept form:
-7x + 7y = -17
7y = 7x -17
y = x - 17/7
So, the slope is 1 and the y-intercept is -17/7
Hope this helps!
You use the slope formula, (y2-y1/x2-x1)
There are 1000 grams in a gram and 1000 times 10 is 10000 so yes 100 mg is less than a 10g