+1839 Point $B$ is the image of point $A$ under a dilation with center $O$. If $OB = 30$, and the scale factor of the dilation is $5$, then what is $OA$?
+1926 There's one important factor we must know to solve this problem.
We have to know the formula
Dilation Factor = Length of Image/Length of Pre-Image.
Well, using this equation, we can easily solve the problem!
Plugging in all the values given in the problem, we have
\(5 = 30 / OA\)
\(OA=30/5\)
\(OA=6\)
So our answer is just 6.
Thanks! ;)
