# Tell weather the graphs pf the pair of equations are parallel, perpendicular or neither.?

Tell weather the graphs pf the pair of equations are parallel, perpendicular or neither.

6x + 6y = 3

6x - 6y = 5

### 4 Answers

- Anonymous1 decade agoFavorite Answer
the pair of eqations a1x+b1y =c1

and a2x + b2y = c2 are

(1.) parallel if a1/ b1 = a2/b2 (derived from equal slopes concept).

(2.) perpendicular if a1a2+b1b2 =0.

the above equation has a1 = 6, b1 =6, a2 = 6., b2 = - 6

clearly, a1a2 + b1b2 =36 -36 =0.

hence,the graphs of the pair of equations are perpendicular.

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- Eliot KLv 71 decade ago
First, put the equations is Y = mX + b form:

9X + 3Y = 14

3Y = 14 - 9X

3Y = -9X + 14

Y = -3X + 14/3

Now you know the SLOPE: -3

when you put the second equation into LINE for (Y=mX+b)

compare the two slopes:(M with M)

if they are the SAME, the lines are parallel (unless the equations are identical, in which case there is only one line)

IF the two SLOPES (Ms) are NEGATIVE INVERSES of each other, they are perpendicular. Examples

-3 is perp. to 1/3

-1/4 is per to 4

by the way, if slope = 0, it's parallel to X axis: Y = 3 is an example

then the perpendicular is the Y axis or X = n, e,.g. X=4.5 or X=-12

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- cidyahLv 71 decade ago
6x + 6y = 3

6y=-6x+3

y= -x+3/6

y=-x+1/2 ----(1)

6x - 6y = 5

-6y=-6x+5

y=x -5/6 ---(2)

The slope of equation (1) is -1

The slope of equation (2) is 1

The product of the slopes is -1

They are perpendicular.

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- 1 decade ago
These two are definitely perpendicular coz the slope of first one is -1 while slope of 2nd one is 1. when the multiplication of slope of two line is -1 then you can say these two as perpendicular. so.....

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