Final answer:
To find the base and altitude of the triangle, set up an equation using the given information and solve for the variables.
Step-by-step explanation:
Let's assume the length of the base of the triangle is 'x'.
According to the given information, the altitude of the triangle is three-fifths of the length of the base. So, the altitude can be expressed as (3/5)x.
When the altitude is decreased by 4cm and the corresponding base is increased by 10cm, the area of the triangle remains the same.
Using the formula for the area of a triangle (A = 1/2 × base × height), we can set up the following equation:
1/2 × (x + 10) × [(3/5)x - 4] = 1/2 × x × ((3/5)x)
Solving this equation will give us the values for the base and altitude of the triangle.