Find x and y x=2y-6 x+2y=7

Can someone check if i did this right since i really want to make sure it’s correct. if you do you so much

The weight of an object in the water is 7% of its weight out of the water. what is the weight of a 652g object in the water?

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?