First, we can represent each of the two equal angles with x. Therefore, since the sum of these two angles equals the last angle, the last angle would be x+x or 2x. Then, since we know the angles in a triangle add to 180°, we can write out a formula and solve for x: x+x+2x=180. First, you need to combine like terms to get 4x=180. Then, you need to divide both sides by 4 to get x=45. Since we know two of our angles are equal to x, then two of our angles are equal to 45°. Then, since the last angle is equal to 2x, it must equal 90° (45*2).
I hope this helps.
