Prescription AnalysisQuestion 31 of 100
Transpose the Rx: +2.00 -1.00 x 090 into plus-cylinder form.
a.+1.00 +1.00 x 180
b.+3.00 -1.00 x 180
c.+2.00 +1.00 x 090
d.+1.00 -1.00 x 090
Explanation
To transpose: add the sphere and cylinder for the new sphere (+2.00 + -1.00 = +1.00), change the cylinder sign (+1.00), and rotate the axis 90 degrees (090 becomes 180). Result: +1.00 +1.00 x 180.
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