The sum of a number and its additive inverse is equal to

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.

Ten times the square of a non-zero number is eqaul to ninety times the number

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? )