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Where do the lines given by y=x+b and y=2x+1 intersect?

1 Answer

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Answer:


x=b-1\\y=2b-1

Explanation:

We have a 2x2 equation system. First, rewrite it like this:


-2x+y=1\hspace{5}(1)\\-x+y=b\hspace{5}(1)

Solving the system using elimination method:

(1)-(2)


-2x-(-x)+y-y=1-b\\x=b-1\hspace{5}(3)

Replacing (3) in (2)


-(b-1)+y=b\\

Adding (b-1) to both sides:


y=b+(b-1)=b+b-1=2b-1

User Andrew Peacock
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