Question

In a parralelogram , length of one side is 10 cm, then the length of opposite side ls?​

Answer 1

Answer:

The length of opposite side is also 10 cm because opposite sides in a parallelogram are equal.

Answer 2

Answer:

We will find the area of △ADC by heron's formula.

s=25+10+8=223=11.5cm

Areaof△ADC=11.5(11.5−5)(11.5−10)(11.5−8)

                                   =19.81

Now, areaof△ADC=areaof△BDC(as triangles on same base and between same parallels are equal in area)

So,areaof△BDC=19.81

              =21×4×BD=19.81

On solving we get BD=9.9cm

So, the other diagonal is 9.9cm