The answer is 210 children tickets were sold . if you multiply the first equation by 7 it would be 7x+7y=2590. then subtract equation 2 from 1 you will have 4x=840 so x=210. Also you can use substitution method.
Answer:
-2
Step-by-step explanation:
15x+6=6x-12
15x-6x=-12-6
9x=-18
x=-2
Answer:
s = - 1 ± 
Step-by-step explanation:
Given
s² + 2s - 6 = 0 ( add 6 to both sides )
s² + 2s = 6
To complete the square
add ( half the coefficient of the s- term )² to both sides
s² + 2(1)s + 1 = 6 + 1
(s + 1)² = 7 ( take the square root of both sides )
s + 1 = ±
( subtract 1 from both sides )
s = - 1 ± 
Thus
s = - 1 -
, s = - 1 + 
Answer:
3.7%
Step-by-step explanation:
We know that from this situation, the probability of drawing a single green marble is 1/3. However, to find the probability of drawing 3 green marbles, we will need to do:

We get a probability of:
This converts to a percentage of:

We get a percentage of 3.7%
Answer:
Step-by-step explanation:
Given x^2+4x+13=0, find the complex roots. The best approach here is to use the quadratic formula. Note that a = 1, b = 4 and c = 13.
Thus, the discriminant, b^2 - 4ac, is (4)^2 - 4(1)(13) = 16 - 52 = -36, and the square root of that is plus or minus i√36, or plus or minus 6i.
plus or minus i√