Answer:
The overall change in field position is 7yds, 0 - 5 + 12 = 7, if that isn't a "sum of integers" I apologize.
Step-by-step explanation:
First substitute .5x in for y to get a solvable equation. You should get 6x+8(.5x)=30. Then multiply 8 times .5 to get 6x+4x=30. Then combine like terms (6x+4x) to get 10x=30 and divide both sides by 10 to get x=3. Then plug this x value (3) into the other equation (y=.5x) to find the value of y. Y=.5(3) so y=1.5. Therefore the answer is B.
Split 33 into two numbers that when added up are 33.
So 12 to 21, which when divided by 3, are 4 to 7.