if the area of triangle ABC equals 528.3 MM squared a equals 21MM and C equals 57° then what is the length of B round your answer the nearest 10th

To find the length of side B, we can use the formula for the area of a triangle:

Area = (1/2) * a * b * sin(C)

We are given the values of the area, side a, and angle C, so we can substitute these values into the formula and solve for side b:

528.3 = (1/2) * 21 * b * sin(57°)
528.3 = 10.5b * sin(57°)
b = 528.3 / (10.5 * sin(57°))
b ≈ 18.6

So, the length of side B is approximately 18.6 mm when rounded to the nearest tenth.