Answer: 75°
Explanation:
The diagram above shows an isosceles triangle because it has 2 equal sides, therefore the two base angles must also be equal.
Hence;
x° + x° + 30° = 180 ( sum of the interior angle of a triangle)
2x° + 30° = 180°
collect like terms
2x° = 180° - 30°
2x° = 150°
Divide bothside by 2
2x°/2 = 150°/2
x° = 75°