Answer: The picture contains the answer and the steps
2,830 x 3 =G three times 0 is 0
2,830 3 times 3 is 9
x 3 3 times 8 is 24 carry the two
8,490 3 times 2 is 6 plus the carried 2 is 8
Multiplication because you are going to multiply the recipe by 2 to double it.
In short, for a vertical parabola, namely one whose independent variable is on the x-axis, usually is x², if the leading term coefficient is negative, the parabola opens downward, and its peak or vertex is at a maximum, check the picture below at the left-hand-side.
and when the leading term coefficient is positive, the parabola opens upwards, with a minimum, check the picture below at the right-hand-side.