Convex Mirror Image Calculation

[roxxyroxx]

Convex mirror problem help??

Homework Statement

a convex mirror has a focal length of 75cm. an object with a height of 2.0m is 6.0m from the mirror.
a) what is the distance from the object's virtual image to the mirror?
b) what is the height of the object's image?

Homework Equations

1/f = 1/do + 1/di

The Attempt at a Solution

1/0.75m = 1/6.0m + 1/di
di = 0.857m

but the answer should be -0.67 for a and i don't know part b

 

[rl.bhat]

Use proper sign convension. Focal length of the convex mirror to be taken as negative.
For second part, use magnification formula. m = di/do

 

[roxxyroxx]

thanks! ^^