Mathematics for IGCSE & O level - Equations (Section 3 - No. 40)
The first angle of a triangle is x, and the second is twice the first. The third angle is 30 degrees. Write an equation to find x (the sum of angles in a triangle is 180 degrees).
x + 2x + 30 = 180
x + x + 30 = 180
x + 30 = 180
2x + 30 = 180
解释
Sum of angles are x + 2x + 30 = 180 degrees