In the standard form of quadratic
the discriminant is
In your quadratic, a = 1, b = -9 and c = -10
Now you need to plug these values into the expression for the discriminant.
Ok, to show that she is incorrect we can use any other number in both equations and they will not be equal. the number she used does turn out equal but that does not mean the equations are equal.
for example
2 times 3=6
3 to the power of 2 is 9
that shows the expressions are not equal
Sum means addition:
So...
1015 + 119 = 1134
Hope this helped!
So this is what's known as a combination. a combination is a group where the order does not matter. to solve a combination, you use this equation:
n! / (r! *(n-r)!)
n is the total number of objects being sorted (8)
r is the group you need to sort them into (4)
(i know it's 2 groups of 4 but if you solve this for 1 group, the other group is automatically made of the remaining kids)
definition of !:
a number with a ! means 1*2*3...*that number (so that number multiplied by every number smaller than it all the way to one)
so we put 8 and 4 in this equation:
8! / (4! *(8-4)!)
simplify:
8! / *(4! 4!)
multiply out:
(8*7*6*5*4*3*2*1) / (4*3*2*1 * 4*3*2*1)
and put that in your calculator
you will get 70
your answer is 70
