The volume of the metal box if the box was completely solid (V1), is:
V1=(12 inches)³
V1=1728 inches³
As there are 3 inches of metal on both sides, the widht if the metal box was not completely solid, is:
W=12 inches-(3 inchesx2)
W=6 inches
Then, the volumen of the no solid metal box is:
V2=(6 inches)³
V2= 216 inches³
Therefore, the volume of metal needed to smelt the cubical metal box, is:
V3=V1-V2
V3=1728 inches³-216 inches³
V3=1512 inches³
Answer:

Step-by-step explanation:
An apothem is a perpendicular drawn from the centre of the triangle to one of its sides.
The three apothems OD, OE, and OF divide ∆ABC into six smaller congruent triangles.
1. Area of ∆OCD
CotOCD = OD/OC
cot30 = CD/6
√3 = CD/6
CD = 6√3
A= ½bh
A = ½ × 6√3 × 6 = 18√3 in²
2. Area of ∆ABC
A = 6 × area of ∆OCD = 6 × 18√3 = 108√3 in²

Answer:
x = 23
Step-by-step explanation:
the sum of the 3 angles in a triangle = 180°
the third angle forms a straight angle with 100°, hence
third angle in triangle = 180° - 100° = 80°
Summing the 3 angles gives
2x + 3 + 80 + 51 = 180
2x + 134 = 180 ( subtract 134 from both sides )
2x = 46 ( divide both sides by 2 )
x = 23