In the figure, $M, N$ and $P$ are the mid points of $AB, AC$ and $BC$ respectively. If $MN = 3\ cm, NP = 3.5\ cm$ and $MP = 2.5\ cm$, calculate $BC, AB$ and $AC$. "
Given:
In the figure, $M, N$ and $P$ are the mid points of $AB, AC$ and $BC$ respectively.
$MN = 3\ cm, NP = 3.5\ cm$ and $MP = 2.5\ cm$.
To do:
We have to calculate $BC, AB$ and $AC$.
Solution:
$\mathrm{MN}=3 \mathrm{~cm}, \mathrm{NP}=3.5 \mathrm{~cm}, \mathrm{MP}=2.5 \mathrm{~cm}$
$\mathrm{M}$ and $\mathrm{N}$ are the mid points of $\mathrm{AB}$ and $\mathrm{AC}$
This implies,
$\mathrm{MN} \parallel \mathrm{BC}$ and $\mathrm{MN}=\frac{1}{2}\mathrm{BC}$
$\Rightarrow 3=\frac{1}{2}\mathrm{BC}$
$\mathrm{BC}=6 \mathrm{~cm}$ Similarly,
$\mathrm{NP}=\frac{1}{2} \mathrm{AB}$
$\Rightarrow \mathrm{AB}=2 \times \mathrm{NP}$
$=2 \times 3.5$
$=7 \mathrm{~cm}$
$\mathrm{MP}=\frac{1}{2} \mathrm{AC}$
$\Rightarrow \mathrm{AC}=2 \times \mathrm{MP}$
$=2 \times 2.5$
$=5 \mathrm{~cm}$
Hence, $\mathrm{BC}=6 \mathrm{~cm}, \mathrm{AB}=7 \mathrm{~cm}$ and $\mathrm{AC}=5 \mathrm{~cm}$.
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