Answer:
Area of the triangle = 210 cm^2 .
Step-by-step explanation:
Perimeter of triangle = 4x + 1 + 3x - 1 + 3x = 70
10x = 70 - 1 + 1 = 70
x = 7.
Area A = 1/2 * base * height
= 1/2 * 3x * (3x - 1)
= 1/2 * 3(7) * (3(7) -1)
= 1/2 * 21 * 20
= 210.
