## careless850 Group Title Solve for x in the proportion 2 years ago 2 years ago

1. careless850

$\frac {4x^{2}}{8x^{2}-8x} = \frac {2}{x}$

2. careless850

Last question for my assignment.

3. redshift

Have you learned cross-multiplication? If so: (x)(4x^2) = (2)(8x^2 - 8x) -expand -collect like terms -isolate for x Does that help?

4. careless850

No.

5. careless850

x = 16 and x = −16

6. careless850

x = 2!

7. redshift

(x)(4x^2) = (2)(8x^2 - 8x) 4x^3 = 16x^2 - 16x 4x^3 - 16x^2 + 16x = 0 4x(x^2 - 4x + 4) = 0 For 4x = 0: x = 0 For x^2 - 4x + 4 = 0: -what multiplies to 4 and adds to -4: -2, -2 x^2 - 4x + 4 = (x - 2)^2 (x - 2)^2 = 0 x - 2 = 0 x = 2

8. careless850

Yes!

9. redshift

and x = 0!

10. careless850

:]

11. redshift

But do you understand!?!?!?!