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I need help with finding areas and perimeter for a trapezoid thank you

I need help with finding areas and perimeter for a trapezoid thank you-example-1
User Schibum
by
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1 Answer

4 votes

Given:

The length of the parallel sides are


\begin{gathered} a=4mm \\ b=6mm \end{gathered}

The altitude is,


h=8mm

To find:

The area and perimeter of the trapezium.

Step-by-step explanation:

Using the area formula of the trapezium,


\begin{gathered} A=(1)/(2)(a+b)h \\ =(1)/(2)(4+6)*8 \\ =(1)/(2)*10*8 \\ A=40mm^2 \end{gathered}

Let us the length of the slant height.

Using the Pythagoras theorem,


\begin{gathered} hyp^2=opp^2+adj^2 \\ hyp^2=8^2+2^2 \\ hyp^2=64+4 \\ hyp^2=68 \\ hyp=√(68) \\ hyp=8.246 \\ hyp\approx8.25 \end{gathered}

Therefore, the length of the slant height is 8.25mm.

Using the perimeter formula,


\begin{gathered} Perimeter=Sum\text{ of all sides' length} \\ P=4+8.25+6+8 \\ P=26.25mm \end{gathered}

Final answer:

The area of the trapezium is 40 square mm.

The perimeter of the trapezium is 26.25 mm.

User Ersen Osman
by
4.4k points