Question

11. The parallel sides of a trapezium are 20 cm and 10 cm. Its nonparallel sides are both equal,
each being 13 cm. Find the area of the trapezium.

this is question of class 8 Rs Aggarwal maths exercise 18A
Give step by step answer then I Markaz braint list ​

Answer 1

if if you have done herons formula then you can do with this method

firstly derived a triangle inside the trapezium

now find the area of the triangle with herons formula

i.e. √s(s-a) (s-b) (s-c)

you can find s by adding all the three sides of the triangle and after that divide them with 2

sites of the triangle are 13 10 and 13

now see, from where did this came

we had 13 given and when we derive the triangle inside the trapezium and we draw that line other side becomes a parallelogram so the other side of the triangle would be also 13 and the bass would be 10

now we will derive everything in this formula

√18×5×5×8

=60cm square

now we will find height

area of ∆=60

1/2×b×h=60

1/2×10×h=69

h=69×2/10

h=13.8cm

area of parallelogram=13.8×10

=138cm square

total area of trapezium=138 + 60

=198cm square

Answer 2

Answer:

trapezium=198 cm sq

Step-by-step explanation:

height=

area of angle =60

1/2×b×h=60

1/2×10×h=69

h=69×2/10

h=13.8 cm

area of parallelogram = 13.8×10

=138 cm

trapezium=138+60

= 198 cm sq

hope it is helpful for you........!!!!