All these equations are in the form of ax^2 + bx + c = 0, where a, b, and c are some numbers. the discriminants of equations like this are equal to b^2 - 4ac. if the discriminant is negative, there are two imaginary solutions. if the discriminant is positive, there are two real solutions. if the discriminant is 0, there is one real solution.
<span>x^2 + 4x + 5 = 0
</span>b^2 - 4ac
4^2 - 4(1)(5)
16-20
-4, two imaginary solutions.
<span>x^2 - 4x - 5 = 0
</span>b^2 - 4ac
(-4)^2 - 4(1)(-5)
16 + 20
36, two real solutions.
<span>4x^2 + 20x + 25 = 0
</span>b^2 - 4ac
20^2 - 4(4)(25)
400 - 400
0, one real solution.
We have

Multiplying through by 1100,


Squaring (which means we need to check later),





Clearly there's no way that giant number would work; must be extraneous.
Answer: 3.94
Merry Christmas!
Answer:
28?
Step-by-step explanation:
For multiple-choice questions, it is often faster to check the answers than to try to figure out what the answer should be.
Only selections (A) and (D) match the first entry in the table.
Of those, only selection (A) matches the second entry in the table.
The appropriate choice is ...
(A) y = x + 9
It’s a!!!!!!!!!!!!!!!!!!!!!!!!