Question

Give exact and approximate solutions to three decimal places. x^2-7x+9=0
I have the exact solutions 1/2 (7-sqrt(13), 1/2 (7+sqrt(13). What are the approximate solutions?

Answer 1

just use a calculator to work them out and then round to 3 decimal places.

Answer 2

or use wolfram alpha: http://www2.wolframalpha.com/input/?i=%287-sqrt%2813%29%29%2F2

Answer 3

So would I key in the solutions as \[x \approx 1.70 and x \approx 5.30\]. Is this correct?

Answer 4

3 decimal places means 3 digits after the decimal point. so your first answer should be:\[x\approx1.697\]

Answer 5

Oooh! Okay.

Answer 6

what you gave was 3 significant digits.

Answer 7

I see. Thank you. :)