Math help? standard form?

determine the equation of the line. Express final equation in standard form Ax+By+C=0





the line through (2,-5) and parallel to the y axis?





the line through (5,-3) and parallel to the x axis?








how do you do determine the equation for these?

Math help? standard form?
first the line through (2,-5) and parallel to the y axis....


because it is parallel to the y axis, that means that the x coefficient (abscissa) is constant....while the y (ordinate) one varies...


so one way is to take another point..(2, y) choose any y.....


for example y=2


now you have 2 pts of the line...


(2,-5) %26amp; (2,2)


get the slope "a" of the line





a=(y1-y2)/(x1-x2)=.../0=infinty....(th... proves that it is parallel to y axis)





(if a= consrtant...


then replace in the equation of a straight line....y=ax+b


you'll get the equation........in the standared form...ax-y-b=0)





so...





we know that its parallel to the y axis so x is constante...


x=2 for every y....so the equation is x-2=0











for the line oassing through (5,-3) and parallel to x axis....





since parallel to the x axis..we should know that the slope a=0





or we can prove it ....by taking another point...(y conatant %26amp; x is changing)....


(x,-3)...and finding the slope.......








finally y=-3......y+3=0
Reply:having a line parallel to the y axis means ya got a vertical line and a vertical line has an equation like x=C;where in C is the constant x coordinate.


answer: x - 2 = 0





parallel to x axis is a horizontal line with a formula y=C like the one in the top.


answer: y +3 = 0
Reply:(2,-5);(5,-3)


write it as an equation


-3-(-5) over 5-2 or





2


__ = slope


3





now the problem says;


y=2/3x +b


now use the (2,-5) or whatever one you prefer


-5=2/3(2) + b


multiply


-5=4/3+b


subtract the 4/2 from the -5


rewrite


-11/3=b


rewrite it in y-intercept form


y=2/3x - 11/3


now subtract the 2/3x to the other side of the equation


always remember to put the x in front of the y


-2/3x + y = - 11/3


in order to get rid of the fraction, you must multiply the entire problem by 3


it will now look like:


-2x + 2y = -11


now to get rid of the negative with the x distribute the negative to the rest of the problem


2x- 2y = 11


that is the answer in standard form!