Solve for di: Negative Effect on Object Distance?

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To solve for the image distance (di) using the formula -di/do = hi/ho, first cross-multiply or multiply both sides by -do. Given the values ho = 3cm, hi = 4cm, and do = 5cm, the calculation leads to di = -6.67cm, indicating the image is inverted. The negative sign in the result signifies that the image formed is real and inverted. Understanding that negative di values correspond to real images clarifies the confusion around the negative aspect of the formula.
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When I'm given do, ho, and hi. How would i solve for di
Normally i would do -di/do = hi/ho and cross-multiply but I'm not sure how the negative comes into effect.

do = object distance
di = image distance
ho = object height
hi = image height



If...

ho = 3cm
hi = 4cm
do = 5cm

What would be di?

Thanks
 
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Please provide the complete statement of the problem you are trying to solve. (I presume that a negative image height means that the image is inverted.)
 
It's just made up values and i want to know how i would solve for di. The negative in the formula confuses me
 
Start with:
-di/do = hi/ho

You can solve for di by cross-multiplying if you like, or just multiply both sides by -do. As I said before, a negative value for di just means that the image is inverted. (Real images are inverted.)
 
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