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Show That: the Ratio of the Areas of Two Triangles of the Same Height is Equal to the Ratio of Their Bases. - Mathematics

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Question

Show that:

The ratio of the areas of two triangles of the same height is equal to the ratio of their bases.

Sum
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Solution

Consider  the following figure:

Here AP ⊥ BC

Since Ar. ( ΔABD ) = `1/2` BD x AP

And, Ar. ( ΔADC ) =`1/2` DC x AP

`["Area"( ΔABD)]/["Area"(Δ ADC )] = [1/2 BD xx AP]/[1/2 DC xx AP]= (BD)/(DC)`

Hence proved.

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Chapter 16: Area Theorems [Proof and Use] - Exercise 16 (B) [Page 201]

APPEARS IN

Selina Concise Mathematics [English] Class 9 ICSE
Chapter 16 Area Theorems [Proof and Use]
Exercise 16 (B) | Q 1.2 | Page 201

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