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Given:
The figures of triangles and their mid segments.
To find:
The values of n.
Solution:
Mid-segment theorem: According to this theorem, mid segment of the triangle is a line segment that bisect the two sides of the triangle and parallel to third side, The measure of mid-segment is half of the parallel side.
9.
It is given that:
Length of mid-segment = 54
Length of parallel side = 3n
By using mid-segment theorem for the given triangle, we get
[tex]54=\dfrac{1}{2}(3n)[/tex]
[tex]2\times 54=3n[/tex]
[tex]108=3n[/tex]
Divide both side by 3.
[tex]\dfrac{108}{3}=n[/tex]
[tex]36=n[/tex]
Hence, the value of n is equal to 36.
10.
It is given that:
Length of mid-segment = 4n+5
Length of parallel side = 74
By using mid-segment theorem for the given triangle, we get
[tex]4n+5=\dfrac{1}{2}(74)[/tex]
[tex]4n+5=37[/tex]
[tex]4n=37-5[/tex]
[tex]4n=32[/tex]
Divide both side by 4.
[tex]n=\dfrac{32}{4}[/tex]
[tex]n=8[/tex]
Hence, the value of n is equal to 8.