Are the lines y = –x – 4 and 5x + 5y = 20 perpendicular? explain.

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Are the lines y = –x – 4 and 5x + 5y = 20 perpendicular? explain.

In second equation, 5x + 5y = 20

5y = -5x + 20

Divide the equation by 5,

y = -x + 4

Here, Slope = -1

Perpendicular line must have slope equal to 1 [ which is opposite & reciprocal ]

But in y = -x - 4, slope = -1 so they are not perpendicular.

In short, Your Answer would be Option D) No, their slopes are not opposite reciprocals.

Hope this helps!

No. they are parallel bc when u turn tge standard form to slope intercept form it is. the same slope diferent intercept

The lines consider perpendicular if (the slope of line 1) * (the slope of line 2) = -1

so get the slope of the lines ,1st put the equation on the form of y = mx+c

where the coefficient of x (m) is the slope

y=-x-4 m1= -1

5x+5y=20

y=-x+4 m2 = -1

so m1 * m2 = -1 * -1 = 1

then, the two lines aren't perpendicular

No the slopes are not equal.

Y=mx+b

m=slope

ax+by=c

-a/b=slope

if slopes muliply to -1 then they are perpendicular

given

y=-1x-4

slope is -1

5x+5y=20

slope=-5/5=-1

-1 timesm -1=1≠-1

not perpendicular

D is answer

Actually no, they are not perpendicular because they both have a negative slope. We know this when we plot points (x,y) to see y= -x-4 5x+5y=20

Please give it a check by this sucession of numbers

( -1, -3 ) (-1, 5 )

( 0, -4 ) ( 0, 4 )

( 1, -5 ) ( 1, 3 )

( 2, -6 ) ( 2, 2 )

( 3, -7 ) ( 3, 1 )

( 4, 8 ) ( 4, 0 )

( 5, -9 ) ( 5, -1 )

I hope this helped you

No. they are parallel bc when u turn tge standard form to slope intercept form it is. the same slope diferent intercept