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Geometry math question no Guessing and Please show work thank you

Geometry math question no Guessing and Please show work thank you-example-1
User Slicekick
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1 Answer

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If AD is the altitude to BC, then AD is perpendicular to BC.

The formula of a slope:


A(x_A;\ y_A);\ B(x_B;\ y_B)\\\\m=(y_B-y_A)/(x_B-x_A)

If
k:y=m_1x+b_1;\ l:y=m_2x+b_2 then
k\ \perp\ l\iff m_1m_2=-1

Calculate the slope of BC:


B(7;\ -2);\ C(3;\ 8)\\\\m_1=(8-(-2))/(3-7)=(10)/(-4)=-(5)/(2)

Calculate the slope of AD:


-(5)/(2)m_2=-1\ \ \ |\cdot\left(-(2)/(5)\right)\\\\m_2=(2)/(5)

Answer: D. 2/5

User Simlmx
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