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## anonymous one year ago Solve equation (Medal to the person who can draw it out) In comments

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1. anonymous

$\sqrt{2x}-4=\sqrt{7x}+9$

2. mathstudent55

Move the roots to one side and the numbers to the other side. Square both sides and simplify. Move the root to one side alone, and everything else to the other side. Square both sides and simplify again. When you find a solution for x, check it in the original equation because squaring both sides of an equation can introduce extraneous solutions. Extraneous solutions are solutions to the squared equation that are not solutions to the original equation.

3. anonymous

I keep getting messed up answers. Either with negatives or decimals

4. mathstudent55

We can do it together step by step if you'd like.

5. mathstudent55

|dw:1434645515589:dw|

6. mathstudent55

|dw:1434645560818:dw| Do you follow so far?

7. MrNood

according to graphing calc these do not have a real solution

8. mathstudent55

|dw:1434645807122:dw|

9. mathstudent55

|dw:1434645882871:dw|

10. mathstudent55

Ok. It turns out that by squaring only once, we got rid of the square root of the variable. Now we need to check the solution in the original equation.

11. anonymous

|dw:1434646453949:dw|

12. MrNood

|dw:1434646063419:dw| therefore no real root

13. mathstudent55

|dw:1434646456165:dw|

14. mathstudent55

|dw:1434646532155:dw|

15. mathstudent55

The solution does not work.

16. MrNood

|dw:1434656606947:dw| These are the 2 graphs they do not intersect

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