Answer:
25
Explanation:
I'll explain in detail for those of you that want to know.
You know that since angles B and C are congruent to each other that this triangle is an isosceles triangle. Therefore, sides AB and AC are congruent to each other because that is a property of an isosceles triangle.
To solve for x, place the expressions of sides AB and AC equal to each other and solve for the unknown variable.
4x + 1 = 2x + 23
You should get that x = 11.
Substitute x = 11 into the expression for side BC to solve for the length of that side.
f(11) = 3(11) - 8
f(11) = 25
Thus, length of side BC is 25 units.
Use this way of solving for all your future questions. It's really simple :)