The negative solution to the problem is -3.
What is an equation?
An equation is an expression used to show the relationship between two or more numbers and variables.
Let x represent the unknown number. When 18 is subtracted from the square of a number, the result is 3 times the number. Hence:
x² - 18 = 3x
x² - 3x - 18 = 0
Solving the quadratic equation gives:
x = -3; and x = 6
The negative solution to the problem is -3.
To know more about equation and square :
brainly.com/question/2972832
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