In a right-angled triangle, the hypotenuse is 5, and one of the legs is 1 larger than the other, find the area of the triangle.
Let’s find the lengths of the legs of this right-angled triangle.
Let’s denote by x the length of the larger leg of this right-angled triangle.
The problem statement says that one of the legs is 1 more than the other. Consequently, the smaller leg is 1 less than the larger leg and its length is x – 1.
According to the condition of the problem, the hypotenuse of this right-angled triangle is 5, therefore, using the Pythagorean theorem, we obtain the following equation:
x ^ 2 + (x – 1) ^ 2 = 5 ^ 2.
Solving this equation, we get:
x ^ 2 + x ^ 2 – 2x + 1 = 25;
2x ^ 2 – 2x + 1 – 25 = 0;
2x ^ 2 – 2x – 24 = 0;
x ^ 2 – x – 12 = 0;
x = (1 ± √ (1 + 4 * 9)) / 2 = (1 ± √49) / 2 = (1 ± 7) / 2;
x = (1 + 7) / 2 = 8/2 = 4.
We find the second leg:
x – 1 = 4 – 1 = 3.
Find the area of the triangle:
4 * 3/2 = 12/2 = 6.
Answer: the area of the triangle is 6.