Respuesta :

Answer: 3.1 cm

Step-by-step explanation:isosollese triangle has 2 equal sides that are longer than legnth of base

perimiter=15.7

equation is 2a+b=15.7

so if the longer side is 6.3, wat is legnth of base

we know that identical sides are bigger so 6.3 is one of the identical sides

2a means the 2 idneical sides

2(6.3)+b=15.7

12.6+b=15.7

subtract 12.6 from btohs ides

b=3.1

answer is base=3.1 cm