In the known triangle ABC, the angle B = 90 °, ab = 3, BC = 4, G is the center of gravity, and the value of BG is obtained
When BG and AC intersect at D, BD is the midline of AC
So BD = 1 / 2Ac
According to Pythagorean theorem, AC = 5
So BD = 5 / 2
Because G is the center of gravity, BG = 2 / 3bd = 2 / 3 * 5 / 2 = 5 / 3
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