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Students in this video, let's learn how to find the area of a general quadrilateral.

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All right.

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Over here we have quadrilateral ABCDE.

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Now let's join point B and point the.

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All right.

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So now you can see that we have got two triangles, right?

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You have Triangle EBD and you have Triangle DBC And from this figure, it's obvious that if you find

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the area of Triangle HDB and added to the area of Triangle DBC, that will be equal to the area of this

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quadrilateral.

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All right.

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Now from Vertex M and Vertex C, let's drop Altitude's to cite Beadie.

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But that would look like this now because these are all dudes.

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These angles are 90 degrees and these sites will be the height of these two triangles.

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Right.

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So let this be a turn and let this be its.

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All right.

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So the area of the quadrilateral is equal to the area of triangle abody, plus the area of triangle

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CBD already.

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And we know that area of a triangle is half base in height.

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Right.

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So therefore this is equal to half beauty into each one plus half beauty into its two.

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Right now, if the length of beauty is taken as deep, then we can see that the area of this quadrilateral

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is equal to half B into X1 plus it's two.

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All right.

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Now, let's apply this in a very simple question.

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Over here.

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You have a quadrilateral and it's given that this diagonal over here is seven centimetre and this altitude

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is two centimeter and this already is three centimeter.

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All right.

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Let's try to find the area of this quadrilateral so we know that the area of this quadrilateral is equal

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to the area of this triangle, plus the area of this triangle over here.

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But that would be half in to seven in the two plus half into seven into three.

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Right.

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Because the area of a triangle is half base height.

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Now, this is equal to half in the seven to two plus three, which gives you seventeen point five centimeters

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square.