Question

Assertion :If the area of an equilateral triangle is $81\sqrt{3}c{m}^2$, then the side of the triangle is $9\sqrt{3}$ cm. Reason: Area of an equilateral triangle is $\frac{\sqrt{3}}{4}{a}^2$ (where a is side of the triangle).

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Assertion is incorrect but Reason is correct

Answer 1

The correct option is D Assertion is incorrect but Reason is correct

We know that, Area of an equilateral triangle is $\frac{\sqrt{3}}{4}{a}^2$ (where a is side of the triangle).
If Area of an equilateral triangle= $81\sqrt{3}c{m}^2$
$\frac{\sqrt{3}}{4}{a}^2=81\sqrt{3}$
$a^2=81\ast 4$
$a=18$
So, Assertion is incorrect but Reason is correct
Answer (D) Assertion is incorrect but Reason is correct.