## Give exact & approx. solns (to 3 dec. places) for (x+8)^2=1

Quadratic equations and inequalities, variation equations, function notation, systems of equations, etc.
think
Posts: 3
Joined: Mon Mar 23, 2009 12:25 am
Contact:

### Give exact & approx. solns (to 3 dec. places) for (x+8)^2=1

Give the exact and approximate solutions to three decimal places
(x+8)^2=1

stapel_eliz
Posts: 1628
Joined: Mon Dec 08, 2008 4:22 pm
Contact:
Give the exact and approximate solutions to three decimal places
(x+8)^2=1
This is probably most-simply solved by taking square roots. For instance:

. . . . .$\left(x\, -\, 5\right)\, =\, 3$

. . . . .$x\, -\, 5\, =\, \pm \sqrt{3}$

. . . . .$x\, =\, 5\, \pm\, \sqrt{3}$

The above would be the "exact" solution. The "approximate" solution would be found by plugging each of:

. . . . .$x\, =\, 5\, -\, \sqrt{3}\, \mbox{ and }\, x\, =\, 5\, +\, \sqrt{3}$

...into your calculator, and rounding the outputs to the required three decimal places.

Note: In this particular case, the "exact" solution won't involve square roots. For the "approximate" solutions, you'll have to tack on three (entirely unnecessary) zeroes after the decimal point.