# Learn Interfaces by Building an Equation Solver - Step 64

### Tell us what’s happening:

Sorry, stuck again. the message “Your solver function should return a different string” isn’t exactly informative or helpful. It doesn’t really give much of a basis to get you to the correct solution. It might as well just say “WRONG!”

### Your code so far

# User Editable Region

details = equation.analyze()
match details:
case {'slope': slope, 'intercept': intercept}:
details_list = [f'slope = {slope:.3f}', f'y-intercept = {intercept:.3f}']
case {'x': x, 'y': y, 'min_max': min_max, 'concavity': concavity}:
details_list = [f'concavity = {concavity}', f'min_max = {x:.3f}, {y:.3f}']
for detail in details_list:
output_string += f'{detail}\n'

# User Editable Region

### Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36 Edg/127.0.0.0

### Challenge Information:

Learn Interfaces by Building an Equation Solver - Step 64

I would check this

The final result should be similar to this <min_max> = (<x>, <y>)

Yes, I see - lacking parenthesis:
`f’min_max = ({x:.3f}, {y:.3f})’ sorts that out but it still doesn’t pass

min_max is a variable, not a string. See how the instructions denote variables in <brackets>

Got it! Thanks - I’m an idiot. It’s been staring me in the face.
Really appreciate that.

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