Question

The area of the triangle whose sides are 42 cm, 34 cm and 20 cm in length is
(a) 150 cm²
(b) 336 cm²
(c) 300 cm²
(d) none of these

pls give the answer with explanation

Answer 1

Answer:

D none of these

Step-by-step explanation:

Answer 2

• As per the given data we have three sides of triangle and find length of triangle.

      Given data:-

       Area of triangle $42cm, 34cm,20cm.$

      To find :- length of triangle(l)=?

       Solution:-

• We know that the triangle has three sides.
• we know that the sum of all three angles is equal to $180degree.$
• we know that sum of two sides is always greater than the third side.
• we know that $a=42cm, b=34cm, c=20cm.$

      Then, we will calculate half of the triangles perimeter,  

          $s=\frac{a+b+c}{2}\\s=\frac{42+34+20}{2}\\s=48.$

•   Now we have to calculate area of triangle,

                       $area=\sqrt{s(s-a)(s-b)(s-c)}\\area=\sqrt{48(48-42)(48-34)(48-20)\\}\\area=\sqrt{48\times6\times14\times28}\\area=336cm^{2}.$

• Hence  length of the triangle is $336cm^{2}$.