X=2y+3.5 is the awnser too this one
The height of a rectangular pyramid is 30 cm.
volume of rectangular pyramid = (length x width x height) / 3
Given:
Volume = 900 cm³
Length = 10 cm
Width = 9 cm
Height = ?
V = lwh/3
900 cm³ = (10cm * 9cm * h)/3
900 cm³ * 3 = (90cm² * h)/3 * 3
2700 cm³ = 90cm² * h
2700 cm³/90cm² = 90cm² * h/90 cm²
30 cm = h
to check:
900 cm³ = (10 cm * 9 cm * 30 cm)/3
900 cm³ = 2700 cm³/3
900 cm³ = 900 cm³
Let the three consecutive equals:
x, x+1, x+2
sum:
x+(x+1)+(x+2) = 36
3x + 3 = 36
x+1 = 36/3
x+1 = 12
x=12-1
x=11
5.) it is already in order
6.)0.3, 3/9, 0.8
7.) 2/16 & 3/24
8.) 4/14 & 6/21