Answer:
B. 45.23 cm
Step-by-step explanation:
perimeter of the figure
║a+9║/7=5
you multiply 7 on both sides which cancel out 7.
now it ║a=9║=35
and now it would be a+9=35 and a+9=-35 then solve it.
35-9 and 9-(-35)= 26 and -44
hope this helped!
213+497=710 total students, so 213 wore a silly hat so that would be 30% wore the silly hats