Answer:
D
Step-by-step explanation:
Using the Cosine rule to find AC
AC² = BC² + AB² - (2 × BC × AB × cosB )
= 18² + 12² - ( 2 × 18 × 12 × cos75° )
= 324 + 144 - 432cos75°
= 468 - 111.8
= 356.2 ( take the square root of both sides )
AC = 
≈ 18.9
-----------------------------------------
Using the Sine rule to find ∠ A
= 
( cross- multiply )
18.9 sinA = 18 sin75° ( divide both sides by 18.9 )
sinA = 
, then
∠ A = 
( ) ≈ 66.9°
Assuming BOD and AOC are straight lines.
Area of the rectangle = 4 x ΔAOD
Area of the rectangle = 4 x 10
Area of the rectangle = 40 unit²
Area of ΔABC = 1/2 x 40
Area of ΔABC = 20 unit²
Answer:
8x
Step-by-step explanation:
Answer:
2520
Step-by-step explanation:
18×24=432
432÷2=216
216×35=7560
7560÷3=2520
Answer:
Step-by-step explanation:
volume=3×3×7=63 inch³
