ok another question...

i need to find out an equation of a line that contains the point (-2,5) and is parallel to the line y=4x-3

if someone could pls tell me how to go about this it would be very helpful cuz as usual im stuck! :mad:

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- Jan 14th 2006, 09:08 AMpianogurl1250lines an equations
ok another question...

i need to find out an equation of a line that contains the point (-2,5) and is parallel to the line y=4x-3

if someone could pls tell me how to go about this it would be very helpful cuz as usual im stuck! :mad: - Jan 14th 2006, 09:18 AMTD!
If the equation of a line is of the form

**y = ax + b**, then a is the slope.

Find the slope of the given line, since parallel lines have the same slope, you have then found**a**.

To determine**b**, fill in the given point for x and y, this will give a lineair equation in b which you can solve.

Also possible: the line with slope**a**through the point (p,q) is given by:**y-q = a(x-p)**. - Jan 14th 2006, 09:21 AMCaptainBlackQuote:

Originally Posted by**pianogurl1250**

gradient of this line, so the required gradient is $\displaystyle 4$.

Therefore the equation of the line is something like:

$\displaystyle y=4x+c$,

for some $\displaystyle c$. The value of $\displaystyle c$ can be determined as

it passes through $\displaystyle (-2,5)$. To do this we put $\displaystyle y=5$ and

$\displaystyle x=-2$ into the above equation and then solve for $\displaystyle c$, ie solve:

$\displaystyle 5=4 \times (-2) +c$

for $\displaystyle c$.

RonL