Respuesta :
Answer: Area of ΔABC = 56m².
Explanation:
Since we have given that
point P∈ AB, such that AP:BP=1:3
Point M is the midpoint of segment CP.
Now, we have given that
Area of ΔBMP=21 m²
Since M is the mid-point of CP, so,
Area of ΔCMP= 21 m².
So, Area of ΔBCP = 21+21=42 m²
According to question,
[tex]\frac{3}{4}\times x= 42\\\\x=\frac{42}{3}=14\\\\\text{ Area of }\triangle APC=14m^2\\\\[/tex]
So, area of ΔABC is given by
[tex]42+14=56m^2[/tex]
Hence, area of ΔABC =56m².

Since M is the midpoint of segment CP, BM is the median of the triangle PBC.
Note that median of a triangle divides it into two triangles of equal area.
Therefore, area (BCP) = 2 × area (BMP)
Given that area (BMP) = 21 [tex]m^{2}[/tex]
So, area (BCP) = 2 × 21 = 42 [tex]m^{2}[/tex] --- (1)
Let h be the height of triangle ABC from the vertex C.
Then, area of Δ ABC = [tex]\frac{1}{2}(AB)(h)[/tex]
Area of Δ BCP = [tex]\frac{1}{2}(BP)(h)[/tex]
Also, since AP : BP = 1 : 3, [tex]BP = \frac{3}{4} AB[/tex]
So, area of Δ BCP = [tex]\frac{1}{2} \frac{3}{4} AB(h)[/tex]
But, from (1) area (BCP) = 42
Therefore, [tex]\frac{1}{2} \frac{3}{4} AB(h)=42[/tex]
[tex]\frac{1}{2} AB(h)=42(\frac{4}{3} )[/tex]
[tex]= 56 m^{2}[/tex]
Hence, area of Δ ABC = [tex]= 56 m^{2}[/tex].
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