Answer:
The sum of the roots is 0.5
Step-by-step explanation:
<u><em>The correct question is</em></u>
What is the sum of the roots of 20x^2-10x-30
we know that
In a quadratic equation of the form
The sum of the roots is equal to
in this problem we have
so
substitute
<u><em>Verify</em></u>
Find the roots of the quadratic equation
The formula to solve a quadratic equation is equal to
substitute
The roots are x=-1 and x=1.5
The sum of the roots are
----> is ok
Answers:
P(A) = 7/12
P(B) = 1/4
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Explanation:
Instead of having one die, let's say we have two dice. I'll make one red and the other blue.
I'll be using the dice chart shown below. The red and blue values add up to the black numbers inside the table. For instance, we have 1+1 = 2 in the upper left corner. There are 6*6 = 36 sums total.
Using that table, we can see the following:
In total, we have 6+5+4+3+2+1 = 21 instances where the two dice add to something larger than 6.
This is out of 36 ways to roll two dice.
Therefore P(A) = 21/36 = (3*7)/(3*12) = 7/12
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If a number is divisible by 4, then it is a multiple of 4.
The multiples of 4 found in the table are: 4, 8, 12
We have
This gives 1+5+3 = 9 values that are a multiple of 4
P(B) = 9/36 = (1*9)/(4*9) = 1/4
