Physics HELP
posted by walter on .
an object 3.00 cm high is placed 20.0cm from a convex mirror with a focal length of magnitude 8.00 cm. Find the position of the image. (Im using 1over20.00 + 1overQ = 1over8.00) and the answer is q= 5.71cm. can someone tell how to do the math.. I suck at algebra

1/20 + 1/q = 1/8
1/q = 0.125 0.050 = 0.175
q = 5.714