Hi! :)
12 a^2 + 60 a - 8
- (16 a^2 - 32 a + 9)
= -4 a^2 + 92 a - 17
So she used

of the cord to make necklaces.

She splits the

length into 4 equal lengths.
To divide a fraction by a fraction, you multiply it by its reciprocal.


She used

of the original chord to make each bracelet.
A Non-example is like there we not enough to grapha
I believe it was a rectangle I'm not sure test it out.