Answer:
see explanation
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
Subtract the sum of the given angles from 180 for B
B = 180° - (90 + 40)° = 180° - 130° = 150°
--------------------------------------------------------------
sin40° =
= 
Multiply both sides by 21
21 × sin40° = a, thus
a ≈ 13.5 ( to the nearest tenth )
--------------------------------------------------------------
cos40° =
= 
Multiply both sides by 21
21 × cos40° = b, thus
b ≈ 16.1 ( to the nearest tenth )
*have
and yes
8 factor
1,2,4,8
9 factor
1,3,9
Side of the square computer screen = 21 inches
It is important to minutely read the details that are already given in the question. the most important information that is given in the question is that the computer screen ia square. Based on this information the answer to the question can be easily deduced.
Then
Area of the computer screen = (Side)^2
= (21)^2 inches square
= 441 inches^2
So the area of the square computer screen is 441 square inches. i hope the procedure is clear enough for you to understand.
Answer: D
Step-by-step explanation: