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Can someone please help me i don't understand this

Can someone please help me i don't understand this-example-1
Can someone please help me i don't understand this-example-1
Can someone please help me i don't understand this-example-2
User Raffobaffo
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1 Answer

26 votes
26 votes

Answer:

Explanation:

equation of finding a midpoint is (x2+x1)/2 and (y1+y2)/2

7) (4+12)/2 = 8 and (9+-4)/2= 2.5

hence midpoint is (8,2.5)

8) we are told the midpoint so we can now find the co-ordinates of the other endpoint:

(5+x)/2= -3

rearrange to find x--> 5+x =-6, so x=-11

(-7+y)/2=2

rearrange to find y--> -7+y=4, so y=11

other endpoint: (-11,11)

5) the gradient of the new equation is parallel to y=3x+7 so it will stay the same

y=3x+c

we know that the points this line passes through is: (-4,-8) so we substitute this into our new equation to find c

-8= (3 x -4) +c

-8=-12 +c

so c= 4

Hence our new equation is y=3x+4

6) perpendicular gradient means that our existing gradient needs to be reciprocated (turned into negative and then flipped)

new gradient is -1/3

y=-1/3x+c

we know the value for x and y so we can substitute into our new equation to find c

9=(-1/3 x -6) +c

9=2 + c

c= 7

Hence our new equation is y=-1/3x+7

Hope this helps!

User An Illusion
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