Question
A triangle has sides 13 cm, 14 cm, and 15
cm. Find the area of the triangle.
Solution
Using Heron’s formula: Semi-perimeter (s) = (13 + 14 + 15)/2 = 21 Area = √[s(s - a)(s - b)(s - c)] = √[21(21 - 13)(21 - 14)(21 - 15)] = √[21 × 8 × 7 × 6] = √7056 = 84 cm² Correct answer: a) 84 cm²
More Triangle Questions
- If perpendicular and base of a right-angle triangle is, 6 cm and 8 cm, respectively, then find the length of the shortest median of triangle.
- Calculate the altitude of an equilateral triangle having each side of length 10√3 cm.
- Two triangles DEF and XYZ are congruent to each other such that DE = 10 cm, YZ = 24 cm, and ∠DEF = ∠XYZ = 90⁰. Find the circumradius of ΔDEF.
- In triangle ABC, DE is drawn parallel to BC, meeting AB at D and AC at E. If AD : DB = 3 : 2 and the area of triangle ADE is 45 cm², find: (a) the area of...
- If the inradius of a triangle with a perimeter of 60cm is 8 cm, then find the area of the triangle.(in cm2)
- Find the length of AC, if ΔABC ~ ΔRQP and BC = 21 cm, QP = 9 cm and RP = 15 cm.
- A △ ABC has sides 5 cm, 6 cm and 7 cm. AB extended touches a circle at P and AC extended touches the same circle at Q. Find the length (in cm) of AQ.
- Find the ratio between the area of an equilateral triangle with side 6 cm and the area of a square with side 6 cm.
- The inner-radius of a triangle is 5 cm, and the sum of lengths of its sides is 60 cm. What is the area of the triangle (in sq. cm.)?
- ∠A, ∠B, and∠C are three angles of ∆ABC.if ∠A-∠B=15°, ∠B-∠C =30°,then ∠ A, ∠B and ∠C are?