tthomas0557 2 years ago Determine if the graphs of the given equations are parallel. y=2x+7 7y+2x=4 what is the slope of the line y=2x+7 what is the slope of the line 7y+2x=4 Are the graphs parallel?

1. surdawi

slope form y = mx + b; m is the slope

2. Fox375

what is the slope of the line 7y+2x=4

3. tthomas0557

Honestly, I am seriosly lost on this question.. I dont even know where to start

4. tthomas0557

so for the first one 2 is the slope?

5. precal

if the slopes are the same, the lines are parallel

6. surdawi

ok try solving for y 7y+2x=4

7. tthomas0557

I feel silly but what would be my first step?

8. surdawi

subtract 2x from both sides

9. tthomas0557

The slope would be -2?

10. tthomas0557

for the first?

11. surdawi

nope write the whole thing 1st equation slope is 2

12. tthomas0557

ok..... so the second would be the same then?

13. surdawi

no, try solving for y, will help u

14. tthomas0557

oh my ok.. let me work this out.. Just a sec

15. tthomas0557

It would be 4?

16. surdawi

nope 7y+2x=4 subtract 2x from both sides

17. tthomas0557

sorry I thought I did.. this is embaressing ... ok just a sec

18. tthomas0557

For some reason I just keep getting 2

19. surdawi

7y+2x=4 -2x -2x 7y = -2x + 4 is that correct?

20. tthomas0557

(4-2x)/7

21. tthomas0557

yes

22. surdawi

correct one extra step y = -2/7x + 4/7 whats the slope

23. tthomas0557

is it undefined?

24. surdawi

y = mx + b m = -2/7

25. tthomas0557

I dont see where I went wrong....

26. surdawi

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27. tthomas0557

Oh ok I see that now. WOW how confusing... I hope I can handle the next on my own.. Thanks for your generous help...

28. tthomas0557

Ok so how would I go about doing a question that asked me this... slope intercept equation of the line whose graph is parallel to y=2x-5 and has te y-interceot (0,9) There is no way I could do that one on my own!

29. surdawi

they are parallel so the slope will stay the same y - y1 = m(x -x1) y - 9 = 2*(x-0) y - 9 = 2x +9 +9 y = 2x + 9