You are correct. The scale factor is 1/5 = 0.2
Nice work.
Your answer should be <span>x>2</span>
You need Pythagorean theorem for this.
a² + b² = c², where c is the hypotheneus and a and b are the sides of the right triangle.
24² + x² = 26²
x² = 676-576
x = ±√100
x = 10 (-10 is rejected because length of triangle cannot be a negative number)