Question

The area of a trapezium is 1920cm². If the height is 30m and one of the parallel side is 40m, find the other parallel side.

Answer 1

Given :

• The area of a trapezium is 1920 m²
• Height → 30 m
• One parallel side → 40 m

To Find :

• The other parallel side.

Solution -

Let the other parallel side be x m.

Provided with area of trapezium, so let's use it's formula.

Formula :

$\large{\boxed{\mathtt{\red{Area\:_{Trapezium}\:=\:{\dfrac{1}{2}\:\times\:(sum\:of\:parallel\:sides)\:\times\:height}}}}}$

➣ $\mathtt{1920\:=\:{\dfrac{1}{2}\:\times\:(40\:+x)\:\times\:30}}$

➣ $\mathtt{1920\:=\:{\dfrac{1}{2}\:\times\:1200\:+\:30x}}$

➣ $\mathtt{1920\:=\:{\dfrac{1200\:+\:30x}{2}}}$

➣ $\mathtt{3840\:=\:1200+30x}$

➣ $\mathtt{3840-1200=30x}$

➣ $\mathtt{2640=30x}$

➣ $\mathtt{\dfrac{2640}{30}=x}$

➣ $\mathtt{88=x}$

$\large{\boxed{\sf{\blue{Other\:parallel\:side\:=\:x\:=\:88\:m}}}}$