Use the formula 0 = b^2-4ac
0 = -b^2-4(2)(-9)
0 = -b^2+72
b^2 = 72
b = square root of 72
b = 2 real numbers
There is an app that will help for these types of questions called, "Showmath."
Answer:
80
Step-by-step explanation:
Answer:
The appropriate hypotheses for performing a significance test is:


Step-by-step explanation:
Last year, the mean score on the state’s math test was 51. The administrators have trained the teachers in a new method of teaching math hoping to raise the scores on this standardized test this year.
At the null hypothesis, we test if the mean score this year is the same as last year, that is:

At the alternate hypothesis, we test if the mean score improved this year from last, that is:

The appropriate hypotheses for performing a significance test is:


Answer:
See, that doesn't make sense.
First of all, 4 is the only number equal to 4. Sp, it'd be 9+4 = 13
Then I'm assuming you're also subtracting 4 from 13, so the answer would be 9.
Hope this helped, have a nice day.