Step-by-step explanation:
The line above the letter means "complement". If X is a set, the the complement of X (denoted by X with a line above it) is the set of all things not in X...If X is a set, then the complement of X (denoted by X with a line above it) is the set of all things not in X.
Sorry if it was complicated
Answer:

Step-by-step explanation:

Answer:
Step-by-step explanation:
Sum of angle in a triangle = 180°
<A+<B+<C = 180
Given <B = 50°
Substituting into the formula
<A+50+<C = 180
<A+<C = 180-50
<A+<C = 130°
Since the ∆ABC is an acute triangle, the angles <A and <C must be angles less than 90° since acute angles are angles less than 90°
The possible values of <A and <C that will be acute and give a sum of 130° are;
∠A= 58° and ∠C= 72°
∠A= 80° and ∠C= 50°
∠A= 60° and ∠C= 70°
You can see that all the Angles are less than 90° and their sum is 130°
A right angle is 90 degrees, an obtuse angle is larger than 90 degrees and an acute angle is less than 90 Degrees.
The angle shown is smaller than 90 degrees so it is c. Acute
If you need to solve for y
10y-12=4
10y=12+4
10y=16
y=16/10=8/5=1 3/5 or 1.6