a = 4, b = -21, c = -18
to keep from getting "mixed up", evaluate the discriminant first ...
b<sup>2</sup> - 4ac = (-21)<sup>2</sup> - 4(4)(-18) = 729
sqrt(729) = 27
x = (21 +/- 27)/8
x = -3/4, x = 6
since the discriminant is a perfect square, the original quadratic will factor ...
4x<sup>2</sup> - 21x - 18 = 0
(4x + 3)(x - 6) = 0
x = -3/4, x = 6
Answer:
c
Step-by-step explanation:
Answer: The missing coordinate -10
Step-by-step explanation: (4,r) = -10
The scenario will will be represented by: 
The number will be -13
Step-by-step explanation:
We have to convert the given situation into the mathematical form
Let x be the number
Then
"a number plus itself"
x+x
"plus twice itself"
x+x+2x
"plus 4 times itself"
x+x+2x+4x
"is equal to -104"

This can also be written as:

Keywords: Linear Equation
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