An isosceles triangle has two sides of length 2x+6. The perimeter of the triangle is 7x+21. What is the ratio of the base to the perimeter?

Answer 1

The base is 7x + 21 - 2(2x+6) = 7x + 21 - 4x - 12 = 3x + 9

The ratio of base to perimeter is (3x+9)/(7x+21) = 3(x+3)/ {7(x+3)} = 3/7

provided x is not -3