Answer:
There are 650 cannonballs
Step-by-step explanation:
If you look closely in the picture, you can see that:
- 1st row has 1 ball
- 2nd row has 4 balls
- 3rd row has 9 balls
- 4th row has 16 balls
etc. etc.
We can see that the number of balls is the square of the row number. There are a total of 12 rows. So, rest of the rows has:
- 5th row has 25 balls
- 6th row has 36 balls
- 7th row has 49 balls
- 8th row has 64 balls
- 9th row has 81 balls
- 10th row has 100 balls
- 11th row has 121 balls
- 12th row has 144 balls
If we add up all those, we get total number of balls:
There are 650 cannonballs
First thing to do is to solve each of these for y. The first one is y=-4x-3; the second one is y=4x-21; the third one is y=4x+21; the fourth one is y=-4x+3. From that you can tell the positive slopes are found in the second and third equations. Those are the ones we will test now for the point (3, -9). y=-9 and x=3, so let's fill in accordingly. The second equation filled in is -9=4(3)-21. Does the left side equal the right when we do the math? -9=12-21 and -9=-9. So the second one works. Just for the sake of completion, let's do the same with the third: -9=4(3)+21. Does -9=12+21? Of course it doesn't. Our equation is the second one above, y+9=4(x-3).
3/4 divided by 1/3 = 3/4 * 3/1 = 9/4 = 2 1/4 <-------reason
Sun Yi can cut out 2 pieces.
Sun Yi will have 1/4 left.
It looks as though you missed a number, but you would factor out an x or a y to get your answer and subtract the whole thing
