Answer:
A = 210 cm²
Explanation:
Perimeter of the triangle = the sum of the sides of the triangle.
70 = (3x - 1) + (4x + 1) + (3x)
70 = 10x
7 = x The length of the sides of the triangle are 3x - 1 = 20; 4x + 1 = 29 and
3x = 21.
Looking at the given information, this triangle is a special type of triangle because the area of a triangle is Area = 1/2 bh and you do not know which side is the base and height of the triangle.
Trying a² + b² = c² to see if it is a right triangle. 20² + 21² = 29 ² ; yes it is a right triangle and now we know that the base and height is 20 and 21. The longest side is the hypotenuse in a right triangle
A = 1/2bh
A = 1/2 (20)(21)
A = 10 · 21
A = 210 cm²