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How do I do this, please explain​

How do I do this, please explain​-example-1
User Sbrk
by
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1 Answer

7 votes

Answer:

1.
y=(1)/(3)x+14

2.
y=1.25x+27

Explanation:

1. The equation of the line passing through the points
(x_1,y_1) and
(x_2,y_2) is


(x-x_1)/(x_2-x_1)=(y-y_1)/(y_2-y_1)

In your case, the line passes through the points (-18,8) and (-9,11). So, its equation is


(x-(-18))/(-9-(-18))=(y-8)/(11-8)\\ \\(x+18)/(-9+18)=(y-8)/(3)\\ \\(x+18)/(9)=(y-8)/(3)\\ \\3(x+18)=9(y-8)\\ \x+18=3(y-8)\\ \\x+18=3y-24\\ \\x-3y+18+24=0\\ \\x-3y+42=0

In the slope intercept form this equation is


3y=x+42\\ \\y=(1)/(3)x+14

2. First, find the slope of the line
4x+5y=1,012:


5y=1,012-4x\\ \\y=202.4-0.8x

Thus, the slope of this line is
m=-0.8

Two perpendicular line have the slopes with their product equal to -1:


m_(\perp)\cdot m=-1\\ \\m_(\perp)=(-1)/(-0.8)=(10)/(8)=1.25

The equation of perpendicular line is


y-y_1=m_(\perp)(x-x_1),

where
(x_1,y_1) are the coordinates of the point the line passes through. So,


y-22=1.25(x-(-4))\\ \\y-22=1,25(x+4)\\ \\y=22+1.25x+5\\ \\y=1.25x+27

User Ekansh
by
6.3k points