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Trapezoid area calculations

Trapezoid area calculations-example-1
User Katspaugh
by
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2 Answers

7 votes

#1

  • 1/2(Sum of parallel sides)Height=Area

Area

  • 1/2(6+14)(5.5)
  • 1/2(20)(5.5)
  • 10(5.5)
  • 55in²

#2

Apply Pythagorean theorem

  • B²=14²-12²=196-144=52
  • B\approx 7

Area

  • 1/2(52+8)(12)
  • 6(60)
  • 360yd²

#3

Area

  • 1/2(Diagonals)
  • 1/2(6+6)(9+3)
  • 1/2(12)12)
  • 6(12)
  • 72ft²
User KJ Sudarshan
by
4.4k points
5 votes

Answer:

Formulas Used


\textsf{Area of a Trapezoid}=(1)/(2)(a+b)h

where:

  • a and b are the bases (parallel sides)
  • h is the height (perpendicular to the parallel sides)


\textsf{Pythagoras' Theorem}: \quad a^2+b^2=c^2

where:

  • a and b are the legs of the right triangle
  • c is the hypotenuse (longest side, opposite the right angle)


\textsf{Area of a Kite}=(1)/(2)pq

where:

  • p and q are the diagonals

-----------------------------------------------------------------------------------------

Question g (Trapezoid)


\textsf{Formula}: \quad A=(1)/(2)(a+b)h


\textsf{Substitution}: \quad A=(1)/(2)(6+14)5.5


\textsf{Answer}: \quad A=55\:\: \sf in^2

Question h (Trapezoid)


\textsf{Formula}: \quad A=(1)/(2)(a+b)h

Find the missing side length of the right triangle using Pythagoras' Theorem:


\implies a=√(14^2-12^2)=√(52)

Therefore, top edge of trapezoid = √52 + 8


\textsf{Substitution}: \quad A=(1)/(2)(√(52)+8+8)12


\textsf{Answer}: \quad A=96+12√(13)=139.3\:\: \sf yd^2\:(nearest\:tenth)

Question i (Kite)


\textsf{Formula}: \quad A=(1)/(2)pq


\textsf{Substitution}: \quad A=(1)/(2)(6+6)(3+9)


\textsf{Answer}: \quad A=72\:\: \sf ft^2

User Prikrutil
by
4.2k points