Answer:
90°
Explanation:
There's are supplementary angles at point C. These are two angles that add up to 180°. We know this because a straight line makes 180° on both sides. Since we know that the first angle is 150°, we can determine the angle a point C is 30°. This is shown by:
180-150=30
So now we know 1 angle and the other two angles are put into like terms (in this case, multiples of x). It is known that the sum of all angles in a triangle equates to 180°. Using this information we can set up a simple equation.
![3x+2x+30=180](https://img.qammunity.org/2022/formulas/mathematics/high-school/hrp7k861neds9p7g6ghdojlgglcbj1iosw.png)
Combining like terms, we get:
![5x+30=180](https://img.qammunity.org/2022/formulas/mathematics/high-school/c3xkq56w4fh0kj4bxkjrontr5xbl752wlr.png)
Isolating x, we get:
![5x=150](https://img.qammunity.org/2022/formulas/mathematics/high-school/elff9z0syydephta99drsc0c2wrc78qoc6.png)
Dividing both sides by 5, we get:
![x=30](https://img.qammunity.org/2022/formulas/mathematics/college/3dw0w0eptuted5s6jy4n5xab3cc5z9aawo.png)
So now we can use this x-value to determine the angle that is being asked. It is shown that angle ABC is equal to 3x. Using the x value we just calculated, we get a final answer of:
![3x=3(30)=90](https://img.qammunity.org/2022/formulas/mathematics/high-school/7v6et3kvkleqyntpfwpb7jbxsjxj66nval.png)
Therefore, the answer is 90°. Hope this helps!