Answer:
-8 or +7
Step-by-step explanation:
Let x represent the number. The the problem statement tells us ...
x² + x = 56
x² +x -56 = 0 . . . . . subtract 56 to put into standard form
(x +8)(x -7) = 0 . . . . factor
Solutions to the equation are values of x that make the factors zero:
x = -8 . . . or . . . x = +7
The number could be -8 or +7.
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Check
For x = -8, the square is (-8)² = 64. Adding -8 to that gives 64-8 = 56.
For x = 7, the square is 7² = 49. Adding 7 to that gives 49+7 = 56.
