Respuesta :

Answer:

x = 10.8

Step-by-step explanation:

We can use the law of sines to solve this problem

sin A         sin B

---------  = ----------

a              b

sin 81        sin 40

---------  = ---------

  x              7

Using cross products

7 sin 81 = x sin 40

Solving for x

7 sin 81 / sin 40  =x

x=10.75599

Rounding to 1 decimal place

x = 10.8