To calculate the area of a triangle you need the base & the altitude to this base:
Area triangle = 1/2(B x H)
Let's draw the altitude A intersecting BC in H. WE get now a right triangle AHB. We know AG = 9.2 we know the angle B =27°, so we can find the altitude AH through trigonometry : sin(B) = opposite side over hypotenuse sin(27°) = AH/AB==> sin(27°) =0.454 ==0.454= AH/9.2==>AH =0.454*9.2