The slopes will be the same but the y-intercept will be different. I graphed out which equation will pass through (4,10) and also be parallel to y=1/2x-8.
The formula for this is . If the diameter is 8 the radius is 4, so filling in accordingly we have and which is and when you multiply in 3.14 you get that A = 401.92 or B above.
. If the diameter is 8 the radius is 4, so filling in accordingly we have 
and 
which is 
and when you multiply in 3.14 you get that A = 401.92 or B above.