Answer:
32°
Explanation:
We want to find the angle B. The first thing we can identify in the question is that AB and AC have the same length of 10 so we can assume that triangle ABC is isosceles
→ If the triangle is isosceles then two angles will be equal
→ Angles in a triangle add up to 180°
We can set up an equation to find the value of B using the information above. If we know that the triangle is isosceles then the base angles are equal and if we know that angles in a triangle add up to 180° we can set up an equation.
→ In equations its important to keep both sides equal and do operations to both sides and not one because then if you do an operation to only one side then you have changed the equation so it's important to do operations on both sides and that's an important rule to bare in mind.
74 + 74 + B = 180
→ Simplify
148 + B = 180
→ Minus 148 from both sides to isolate B
B = 32°
So the measure of B is 32°