If x=-7 is a root of the equation x^2+kx+49=0, then k=

Find the domain of the following expression: 1/(√x)-2

Graph the line that represents a proportional relationship between d and t with the property that an increase of 33 units in t corresponds to an increase of 44 units in d. what is the unit rate of change of dd with respect to t? (that is, a change of 11 unit in t will correspond to a change of how many units in d? )

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