Question

The area of trapizium is 15.4m².if one parallel side is 5m less than twice the other side and the distance between theh is 1.4m find the length of both of the parallel side .. plz answer this with all steps. This is a classs 8 CBSE question ​

Answer 1

Given :

• Area of Trapezium is is 15.4 m² .
• One parallel side of Trapezium is 5m less than twice the other side .
• Distance between the parallel sides is 1.4 m .

To Find :

• Length of parallel sides of the Trapezium .

Solution :

$\longmapsto\tt{Let\:one\:parallel\:Side\:be=x}$

As Given that one parallel side of Trapezium is 5m less than twice the other side . So ,

$\longmapsto\tt{Other\:Side=2x-5}$

$\longmapsto\tt{Height=1.4\:m}$

Using Formula :

$\longmapsto\tt\boxed{Area\:of\:Trapezium=\dfrac{1}{2}\times{(Sum\:of\:Parallel\:sides)}\times{h}}$

Putting Values :

$\longmapsto\tt{15.4=\dfrac{1}{2}\times{(x+2x-5)}\times{1.4}}$

$\longmapsto\tt{15.4=\dfrac{1}{2}\times{(3x-5)}\times{1.4}}$

$\longmapsto\tt{15.4\times{2}=3x-5\times{1.4}}$

$\longmapsto\tt{30.8=3x-5\times{1.4}}$

$\longmapsto\tt{\dfrac{308\times{{\cancel{10}}}}{14\times{{\cancel{10}}}}=3x-5}$

$\longmapsto\tt{\cancel\dfrac{308}{14}=3x-5}$

$\longmapsto\tt{22+5=3x}$

$\longmapsto\tt{27=3x}$

$\longmapsto\tt{x=\cancel\dfrac{27}{3}}$

$\longmapsto\tt\bf{x=9}$

Value of x is 9 .

Therefore :

$\longmapsto\tt{Length\:of\:one\:side=x}$

$\longmapsto\tt\bf{9\:m}$

$\longmapsto\tt{Length\:of\:other\:side=2(9)-5}$

$\longmapsto\tt\bf{13\:m}$

Answer 2

Question :-

The area of trapizium is 15.4m².if one parallel side is 5m less than twice the other side and the distance between theh is 1.4m find the length of both of the parallel side ..

Answer :-

Length first side = 9m .

Second side = 13m .

Given :

Area of Trapezium is = 15.4 m² .

One // side of Trapezium is 2x - 5 .

Distance = 1.4 m .

Have to Find :

What are the measurement of Length of parallel side.

Solution :

So ,firstly we consider one parallel Side = x

Now from the given --

One side given as 2x-5

Distance =1.4m

Now As we know the Formula of area of trapezium

Area of Trapezium = 1/2 ( sum of parellel sides ) × height

Therefore ,

↠ 15.4= 1 / 2 × (x+2x-5) × 1.4

↠ 15.4= 1/2 × (3x-5) × 1.4

↠ 15.4 × 2 = 3x - 5 × 1.4

↠ 30.8 = 3x - 5 × 1.4

↠ ( 308 × 10) / ( 14 × 10 ) = 3x - 5

↠ 308 / 14 = 3x - 5

↠ 22 + 5 = 3x

↠ 3 x = 27

↠ 27 / 3

$\large{\boxed{\bold{x\:=\:9\:m}}}$

• Length of one side = x = 9m
• Other side = 2 × 9 -5

= 13m .