Answer:
and 
Step-by-step explanation:

Discriminant

If the discriminant is a negative number then the roots of the equation are imaginary

So, the two solutions are
and 
Answer:
x (children) = 58
y (students) = 66
z (adults) = 29
Step-by-step explanation:
Step 1: Write system of equations
x + y + z = 153
5x + 7y + 12z = 1100
1/2x = z
The best way to solve the systems of equations is to use an augmented matrix:
Top row: [1 1 1 | 153]
Middle row: [5 7 12 | 1100]
Bottom row: [1/2 0 -1 | 0]
And then put it in RREF form:
Top row: [1 0 0 | 58]
Middle row: [0 1 0 | 66]
Bottom row: [0 0 1 | 29]
To download 5 albums it would be $60.
Explanation: $36 divided by 3 is $12.
5 x $12= $60.
-1 is the first answer and for #2 is the 4th answer.
Please let me know if you need additional help in private messages
Thanks,
-GeVontae The BRAINLY Team.
Answer:
A. 3x^2+7x^2+2×3x ×7-84x = 3x^2+7x^2-2×3x×7
9x^2+49x^2+42x-84 x= 9x^2+49x^2-42x
9x^2+49x^2-42 = 9x^2+49 x^2-42x
verified
B.