Answer:
- x = -1/2(1 +√21) ≈ -2.79129
- x = -1/2(1 -√21) ≈ 1.79129
Step-by-step explanation:
We assume the middle term is supposed to be 4x.
We can remove a common factor of 4 to simplify this a bit.
x^2 +x -5 = 0
This is of the form
ax^2 +bx +c = 0
where a=1, b=1, c=-5.
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The <em>quadratic formula</em> gives the solutions as ...

Filling in the given coefficients, we have ...
x = (-1 ±√(1^2 -4·1·(-5)))/(2·1)
x = (-1±√21)/2
The solutions are x = -1/2(1 +√21) and -1/2(1 -√21).
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<em>If what you wrote is what you intend</em>, then the equation simplifies to 4x^2 -16 = 0.
Dividing by 4 and factoring the difference of squares gives ...
x^2 -4 = 0
(x -2)(x +2) = 0
These factors are zero (hence their product is 0) for the values x = 2 and x = -2.
The solutions are x=2 and x=-2.
The equation that can be used to determine the measure of ∠A is tanA = 9.4/6.7. The correct option is A. tanA=9.4/6.7
<h3>Trigonometry</h3>
From the question, we are to determine which of the given equations can be used to determine the measure of ∠A
In the diagram,
If ∠A is the included angle
Then,
Using<em> SOH CAH TOA</em>
Opposite = 9.4
Adjacent = 6.7
Thus,
tanA = 9.4/6.7
Hence, the equation that can be used to determine the measure of ∠A is tanA = 9.4/6.7. The correct option is A. tanA=9.4/6.7
Learn more on Trigonometry here: brainly.com/question/2673715
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Answer: 210
Step-by-step explanation:
We know that the number of combinations of n things taken r at a time is given by :-

So, number of ways to select 3 plants out of 7 = 
Also number of ways to arrange them in 3 positions = 3! = 6
Now , total number of arrangements with 1 plant in each spot = (number of ways to select 3 plants out of 7) x (number of ways to arrange them in 3 positions)
= 35 x 6
=210
Hence, required number of ways = 210
Divide 24 from both sides