what is joint equation of two straigt lines/If we plot graph of that combined equation,what will be  nature?
606971
Do they have the same slope?  If so:\n\n(Y2-B2)/X2 = (Y1-B1)/X1\n\nThis implies that they will either never intersect or be equal to each other. (ie, if B2=B1, they are the same, if B2=/=B1 they will never be equal.)\n\nOK, so you have updated the question.  Now if you multiply these two equations together you will notice that x will be 2nd degree and y will be second degree (ie, both will have a 2 as their largest exponent.)  Therefore, the graph will be one of a conic section.  Either and ellipse, a circle, a hyperbola, or a parabola depending upon the scalars a,b,c and A,B,C.  If you don't know how to tell when a conic section is a circle, ellipse, hyperbola, etc. then ask another question, or google it.  Hope this helps.
924939
yes take the slope of both lines  \nthen if same slope, they are parallel\nif negative reciprical, they are perpendicular,\nif neither, they are neither....\n\nbtw.... m = change in y divided by change in x.....\n    or (y2-y1)/(x2-x1)
653148
All equations for a line will have the form:\n\ny = mx + b,\n\nwhere x & y are coordinates, m is your slope, and b is your y-intercept.\n\nTherefore, substituting in your slope and y intercept, you get:\n\ny = -2/3x + 4\n\nThis equation can then be used to graph the line, since given any x, the corresponding y can be found. :)
623659
Lines with undefined slope are always in the form x = a, where a  is any real number. This is a vertical line, where the the value of x is constant, not dependent on y.\n\n\nSince an ordered pair is in the form (x,y)....in the ordered pair (4,-2), x = 4\n\nSo your equation is x = 4
807353
Just an idea:\n\nthe two tangency points are related by the fact that the slope from point Pf to Pg is the slope of the line AND the derivatives at those two points. \n\nYou have 2 free variables: the x coords of Pf and Pg.  From these the y coords are given by the function values and the slopes are given by the derivatives at those values.  There should be enough relationships to allow solution.
1134198
Slope of the given line AB= [2-3]/[-2-2]= 1/4\n\nSlope of the required line= -1/4.\n\nThe required equation y= (-1/4)*x + constant.\n\nInfact this is the equation for family of lines which met the above condition.
543118
No, you must use algebra to plot lines. How else would you explain the variables x and y?\n\nSlope-intercept form looks like this:\n\ny = mx+b\n\nOr, in the case of vertical lines:\n\nx = my+b\n\nWhere m is the slope and b is the x- or y- intercept, depending on which one you are using.
528541
The slope is zero, it is a horizontal line.  The equation is y=-3.\n\ny=mx+b is the slope intercept form where m is the slope and b in the place where the line crosses the y axis.\n\nSlope is rise over run. The is the difference in y's over the distance in x's.
896230
the y coordinates are the same i.e. -1, \nso the line is parallel to the x axis and passes through -1 on the y axis.\nits slope is parallel to the x axis.
871684
The graph of this equation looks like a V. It's the same as the graph of y=2x, except that the part which should bein quad III is actually in quad II.\nFor this graph, the vertex is when y=0. \nSo the vertex is at (0,0).
179699
The equation of a line is y=mx+c\nHere when x = 6, m = 4/3, y = -2\nTherefore c = y-mx = -2 - (4/3)*6 = -10\n\nHence y = (4/3)x-10\n\nHope this helps!
818092
When Graphed\n\nEquations can be any line\nLinear Equations form only straight lines\nFunction is only a function if you don't have 2 identical x values.
826055
First pair both x values are the same so it is a vertical line through -5 on the x-axis. Which would mean it has no slope (undefined)\n\nSecond pair has identical y-values so it is a horizontal line (slope=0) through 3 on the y-axis\n\nFor the third pair us the formula \ny=mx+c which describes any straight line (m=slope, c= a constant distinguishing the line from others with the same slope in different locations on a graph)\n3=m(-8)+c      (a)\n2=m(-6)+c      (b)\nSimultaneous equations!\nc=3+8m           (a)\n2=-6m+3+8m   (sub (a) into (b))\n2m=-1\nm=-1/2  \nSo the slope = -1/2\n\nThis formula can be used for any problem like this using the same method.
1093431
what is d2 here..if its line what is its equation?
850129
Firstly, determine the slope or gradient of the lines;\n\nLine 1:\n\nm1 = (y2-y1)/(x2-x1)\n     = (3 - -7)/(1 - -4)\n     = 10/5\n     = 2\n\nLine 2:\n\nm2 = (y2-y1)/(x2-x1)\n    = (10 - 6)/(4 - 2)\n    = 4/2\n    = 2\n\nBoth gradients are the same, therefore the lines are parallel. if the product of the gradients (m1m2) was -1 then they would have been perpendicular.\n\nWe can take this further by checking to see if they are the same line.\n\nThe equation y - y1 = m(x - x1) will be the same for both lines if this is the case.\n\nLine 1:\n\ny - 3 = 2(x - 2)\ny = 2x + 1\n\nLine 2:\n\ny - 10 = 2(x - 4)\ny = 2x + 2\n\nThese are not equal, however we now know that line 2 sits 1 unit higher on a graph than line 1, and both lines are parallel to each other.
763572
Hi!\n\nSo, what you are looking at is a linear equation.  You can tell this because there is only one instance of the variable x, and it is not raised to any power.  So, the graph will take the form of a line.\n\nAll linear equations take the form f(x) = mx + b\n\nWhere m is typically called the "slope" and b is called the "y-intercept".   The y-intercept is the point on the graph where the function intercepts the y-axis (the one that goes from top to bottom on the graph).  So, right away you can tell that the y-intercept in your equation is -5 (negative 5).  What this means is that the graph intercepts the y-axis at the -5, or in other words, there is a point on the graph at the location (0,-5).  You can put a dot there.\n\nThe next thing you need to see is the slope.  In you equation, the slope is -2 (negative 2).   Slope really means "rise over the run", or in other words, how much the graph rises for every point it goes to the right.  A slope of negative 2 means that for every increase in x of one unit, the y value decreases by negative 2.   \n\nSo, starting at the point (0,-5) which we determined above, go down 2 units and to the right one unit (putting you at the point (1,-7).  That's another point.  You can do it again and find the next point which is (2,-9) and put another point.  You now can put your ruler on the graph and draw the rest of it.\n\nIt's good to understand how this type of equation works.  You could have also made a table of x values and y values, and simply computed a series of y values for a series of x values (that you picked).  Then you could have drawn the graph also.  But understanding this type of equation will help you in the future.
152511
Which function, Subsitution, Linear COmbination, Graph?