



 
Hi Lisa, If you have the equation of a line in the form y = mx + b then you know immediately that the slope of the line is m. Similarly if you know that a line has slope m then you know that there is a number b so that the equation of the line can be written y = mx + b. I'm going to solve a problem that is similar to yours.
I am going to first write the equation 3x + 4y = 5 in the form y = mx + b since that will tell me the slope.
add 3x to both sides
divide both sides by 4
This is in the required form y = mx + b so I know that m = 3/4 is the slope of the given line. Parallel lines have the same slope so the line I am seeking also has slope m = 3/4. Thus there is some number b so that the line I want is y = 3/4 x + b. All that remains is to find b. The extra fact I know is that the point (2, 3) is on this line, so substituting x = 2, y = 3 I get
and hence
Hence the equation of the line parallel to 3x + 4y = 5 and containing (2, 3) is
Now you try your question. Penny  


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