Parentheses

class Parentheses1(Scene):
    def construct(self):

        paren = Parentheses("x")
        self.add(paren)

        paren.input.set_color(BLUE)
        paren.parentheses.set_color(WHITE)

Distributive Property

class DistributiveProperty(Scene):
    def construct(self):

        a, x, m, y = MathTex("a", "x", "-", "y")

        tex = MathTex(a, Parentheses([ x, m, y ]))
        self.add(tex)

        m.save_y()
        tex.terms = [[a, x], m, [a, y]]
        m.restore_y()
        self.play(TransformInStages.progress(tex, lag_ratio=0))