If you have teaching textbooks and your done with the third cd can you me with this answer 2 divided 613

Which expression is equivalent to the expression shown?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

Recall that the owner of a local health food store recently started a new ad campaign to attract more business and wants to know if average daily sales have increased. historically average daily sales were approximately $2,700. the upper bound of the 95% range of likely sample means for this one-sided test is approximately $2,843.44. if the owner took a random sample of forty-five days and found that daily average sales were now $2,984, what can she conclude at the 95% confidence level?