The first few steps in solving the quadratic equation 8x2 + 80x = −5 by completing the square are shown.

8x2 + 80x = −5

8(x2 + 10x) = −5

8(x2 + 10x + 25) = −5 +

which number is missing in the last step?

Use a calculator to verify that σ(x) = 62, σ(x2) = 1034, σ(y) = 644, σ(y2) = 93,438, and σ(x y) = 9,622. compute r. (enter a number. round your answer to three decimal places.) as x increases from 3 to 22 months, does the value of r imply that y should tend to increase or decrease? explain your answer. given our value of r, y should tend to increase as x increases. given our value of r, we can not draw any conclusions for the behavior of y as x increases. given our value of r, y should tend to remain constant as x increases. given our value of r, y should tend to decrease as x increases.