What does this equal 3(x+4)

Since the 3 is outside of the parentheses you would have to distribute it. This means that you multiply x by 3, then you multiply 4 by three to get 3(x) + 3(4). SO 3 time x equals 3x plus 3 time 4 equals 12
 This would give you 3x+12

2.
Assume the quadrilateral is a square.
Then m<4 = 90
m<5 = 45
m<6 = 45

16.
Assume it's a regular hexagon.
The hexagon can be divided into 6 congruent equilateral triangles.
The 3 sides of each equilateral triangle measures 6sqrt(3) m.
When you draw a segment from the center of the hexagon to a side of the hexagon, you divide one of the 6 triangles into 2 30-60-90 triangles. The ratio of the lengths of the sides of a 30-60-90 triangle is 1 : sqrt(3) : 2. That segment is also the height of one of the 6 triangles.
height = (6sqrt(3))/2 * sqrt(3) = 9
Now we know the base and height of one of the 6 triangles.The area of the hexagon is 6 times the area of one triangle.

area of hexagon = 6 * bh/2
area of hexagon = 6 * 6sqrt(3) m * 9 m/ 2 = 324sqrt(3) /2 m^2 = 162sqrt(3) m^2