Answer:
5
Step-by-step explanation:
Given the following angles ∠BOC=x+3, ∠AOB=4x−7, and ∠AOC=21, the expression is true about the angles;
∠AOC = ∠BOC+∠AOB
Substituting the given values into the expression, we will have;
21 = x+3+4x-7
collect the like terms
21 = x+4x+3-7
21 = 5x-4
Add 4 to both sides
21+4 = 5x-4+4
25 = 5x
Divide both sides by 5
5x/5 = 25/5
x = 5
Hence the value of x is 5
