Question

EXERCISE 17.1
LEVEL-1
RD SHARMA

1. Find the area of a triangle whose sides are respectively 150 cm, 120 cm and 200cm
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Answer 1

Answer:

Step-by-step explanation:

ANSWER:

To find the area of a triangle we use

HERON'S FORMULA.

In this we fins the semi perimeter and then bring out the area by Subtracting the semi perimeter and side and then put a root on them.

STEP 1:-

Finding semi perimeter:

s = $\frac{a+b+c}{2}$ where a b and c are the respective sides.

s = $\frac{150+120+200}{2} = \frac{470}{2} = 235$ is the semi perimeter .

STEP 2:-

Now ,  subtracting sides ie,

(s-a) = 235-150 = 85

(s-b) = 235-120 = 115

(s-c) = 235-200 = 35

STEP 3:-

Now we know that:

$\textsf{Area of a Triangle}$ $= \sqrt{s(s-a)(s-b)(s-c)}$ (According to Heron's formula)

Placing the values,

$\sqrt{235*85*115*35} = 8966.569 m^{2} \textsf{(Approx.)}$

Answer 2

Answer: the answer is 8966.57cm²

Step-by-step explanation:  let

          a=the first side=150cm

          b=the second side=120cm

          c=the third side=200cm

          s=semi-perimeter=(a+b+c)÷2

                                        ⇒150+120+200/2

                                         ⇒470/2=235

now, area of the triangle=√s(s-a)(s-b)(s-c)

                                = √235(235-150)(235-120)(235-200)  

                                =√235(85)(115)(35)

                                =√8,03,99,375

                                =8966.57cm²

Therefore,area of the triangle=8966.57cm²