Question 777529
121 = 100 * (1 + x)^2, solving for x. 

So far, I've come down to this expression...

121 = 100 * (1 + x)(1 + x)

121/100 = 1 + x + x + x^2

121/100 = 1 + 2x + x^2

To get rid of the 1...
Multiply the 100 again...

121 = 100 + 200x + 200x^2

Subtract the 100 on both sides...

21 = 200x + 200x^2

Divide by 200...

.105 = x + x^2

This is where I'm stuck with above.


You got stuck because {{{100}}} * {{{x^2}}} DOESN'T equate to {{{200x^2}}} ------ Multiplying {{{121/100 = 1 + 2x + x^2}}} by 100.