Question

Is the line y = 3x – 7 parallel or perpendicular to 3x + 9y = 9? Explain your answer.

Answer 1

are the slopes the same?

Answer 2

@Brandon78 ?

Answer 3

I don't know it just asked me that

Answer 4

https://www.desmos.com/calculator

I use this really cool graphing calculator that my teachers gave me the link for. If you type in your equation, the calculator will graph it. Then you can find out if the lines are parallel or perpendicular.

Remember:
Perpendicular-intersect
parallel-never meet.

Answer 5

I don't have a calculator i am home schooled online.

Answer 6

The second equation solved for y:\[y=1-\frac{x}{3} \]The slope of the above line is minus the reciprocal of 3, hence, the second line is perpendicular to the first line.

Answer 7

without using calculator, you should take account that parallel lines have the same slop or the same gradient. the gradient for the first line is 3 and that of the second, after re-writing it in terms of y is -1/3.
When two lines are perpendicular, one is the negative inverse of the gradient of the other, which is exactly the case. 3 is the negative inverse of -1/3. therefore are perpendicular.