Answer:
a=1.5, b= 3
Explanation:
sum of all sides will give us perimeter. Therefore
2a+b+6a+2b+1+4a=28
12a+3b+1=28
12a+3b=27....eqn1
since t two sides of this isosceles triangle are equal:
2a+b=4a
2a=b

substituting

in the first equation whenever we encounter a we will have:

6b+3b=27
9b=27
b=3
therefore
