Explanation
Correct answer: 11.
It's given that the graphs of the equations in the given system intersect at the point , where is a constant. Therefore, the coordinates of this point must satisfy both equations. Substituting the point into the first equation, , yields . Adding to both sides of this equation yields , which is equivalent to . Substituting the point into the second equation yields . Substituting in place of in the equation yields . Applying the distributive property to the left-hand side of this equation yields . Combining like terms on the left-hand side of this equation yields . Subtracting from both sides of this equation yields . Dividing both sides of this equation by yields .
Desmos solution:
Enter in Desmos:
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