Question

Need help on both problems.

Answer 1

1)
use Pythagoras, so that
${18}^{2} - {10}^{2} = 224$

the square root if 224 is 14.96662955
so roughly, she needs 15ft for the remaining side.
15+10+18=43

so the answer is c.

2)
first calculate the length through the pond

36^2+49^2=3697
square root of 3697 =60.80296045

36+49=85
85-60.80296045=24.19703955

so he saves about 24.2m