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What is the common difference in the following arithmetic sequence 7,3,-1,-5

1.two more than the quotient of a number and 6 is equal to 7 use the c for the unknown number translate the sentence into an equation

Amodel rocket is launched from a roof into a large field. the path of the rocket can be modeled by the equation y = -0.04x^2 + 8.6x + 4.8, where x is the horizontal distance, in meters, from the starting point on the roof and y is the height, in meters, of the rocket above the ground. how far horizontally from its starting point will the rocket land? a. 0.56 m b. 215.56 m c. 431.11 m d. 215.74 m