We enlarge the circular flower bed, so its radius increased by 3 m. The substrate consumption per enlarged flower bed was (at the same layer height as before magnification) nine times greater than before. Determine the original flowerbed radius.

Correct answer:

r1 =  1.5 m

Step-by-step explanation:

r2=r1+3 S2=9 S1 πr22=9 πr12 r22=9 r12 r2=3 r1  r2=r1+3 r2=3 r1  r1r2=3 3r1r2=0  r1=32=1.5 m r2=92=4.5

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