7 is the right answer(please rate 5.0 stars so i can help other people out thanks)
As the ratio of your shadow to your height is 2:1 assuming the flagpole would form a similar triangle the shadow is twice the height of the pole meaning the pole is 14 feet tall
So permiter=masure of all sides added together
so sides are(3x+2), (2x+5), and (4x)
so (3x+2)+(2x+5)+(4x)
use associative property
a+(b+c)=(a+b)+c so
(3x+2)+(2x+5)+(4x)=3x+2+2x+5+4x
group like terms becasue can move numbers around
(3x+2x+4x)+(2+5)
add like terms
(9x)+(7)
9x+7
he will use 9x+7=perimiter
There are 12 inches in 1 foot, and each bracelet takes 6 inches
12 divided by 6 = 2
there can be 2 bracelets per foot of yarn
5 x 2 = 10 bracelets can be made
let me know if you have any further questions
:)