First, solve for each of the angles. Since it is a right triangle, one of the angles is 90 degrees. Knowing that the sum of the angles of a triangle are always equal to 180 degrees, you can write an equation for the triangle.
Angle1+ angle2+angle3=180.
Which means that 90+(x+15)+2x=180.
After finding the value of x, which is 25 in this case, solve for each angle.
X+15=25+15=40.
2x=25*2= 50
The value of the smallest angle is 40 degrees.