Given the following angles of the triangle:
< 90°, < 30°, and < 2x °, and that the sum of all angles must equal 180°, to setup the equation for x, we must create an equality statement:
< 90° + < 30° + < 2x° = 180°
Now, to isolate 2x:
We need to subtract < 90° and < 30° from both sides:
< 90° - < 90° + < 30° - < 30° + < 2x° = 180° - < 90° - < 30°
2x° = (180° - < 90° - < 30°)
Next, we must divide both sides by 2 to isolate x:
2x°/2 = (180° - < 90° - < 30°)/2
Therefore, the equation for x is:
x=(180-90-30)/2