triangle ABC is a right angled at B and D is the mid point of BC.prove that 2AC=4AD+AD_3AB+AB
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[FIGURE IS IN THE ATTACHMENT]
GIVEN:
ABC is a right angled at B and D is the midpoint of BC.
In ∆ABD
AD²= AB²+BD²…………(1)
[By Pythagoras theorem]
In ∆ ABC
AC²= AB²+BC²…………(2)
From equation (1)
AD²= AB²+ (BC/2)²
[D is the midpoint of BC]
AD²= AB²+ BC²/4
AD²= AB²/1+ BC²/4
4AD²= 4AB²+ BC²
BC²= 4AD²-4AB²…………….(3)
Using the value of BC² in eq. 2
AC²=AB²+4AD²-4AB²
AC²=AB²-4AB+4AD²
AC²= 4AD²-3AB²
HENCE PROVED….
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