Answer:
x= to 5
Step-by-step explanation:
Use a calculator called symbolab.com
x/10 + x/4 = 21 /*40
4x + 10x = 840
14x = 840
x = 60 = total number of points the team scored
I could be wrong, but I'm pretty sure here the answer would be 10x^2 + 17x +3 would be the area since you have to multiply length and width. since these are expressions with no answers and no other numbers, we can't find x.
For this case we have by definition of trigonometric relations of rectangular triangles that, the sine of an angle is given by the opposite leg to the angle on the hypotenuse of the triangle. Then according to the figure we have:

We cleared CA:

Answer:
Option A