In the standard form of quadratic
the discriminant is
In your quadratic, a = 1, b = -9 and c = -10
Now you need to plug these values into the expression for the discriminant.
Answer:
x ∈ {-5, -1}
Step-by-step explanation:
Here's the solution using the quadratic formula:
The real zeros are -5 and -1.
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There are many ways to check your answer. One of them is to look at the given quadratic, which has no changes of sign in its coefficients. (They are all positive.) That means there can be no positive real roots, so already you know that x=0.5 won't work.
Also, the constant in the quadratic is the product of the roots, For your roots, their product is -7/4, so even multiplying by 4 (the leading coefficient in the given quadratic), you don't get anything like 20.
SohCahToa
Sin=oposite side/hyptoonuse
Cos=adjacent side/hypotonuse
Tan=oposite side/hypotonuse
oposite side is the side oposite the angle
adjacent side is the side touching the angle that isn't the hypotonuse
hypotonuse is longest side
1.
first solve for hypotonuse using a²+b²=c²
hypotonuse=13
sinA=12/13
cosA=5/13
tanA=12/5
sinB=5/13
cosB=12/13
toa=5/12
2. the missing side is 8
sinD=15/17
cosD=5/17
tanD=15/5=3
sinE=5/17
cosE=15/17
tanE=5/15=1/3
3. missing side is 25
you should be able to do this
sinG=7/25
do the rest
4.
missing side is 6
sinJ=6/10=3/5
do the rest
Answer:
x = 3 and y = -3
Step-by-step explanation:
To start, let's double the first equation to get 6x + 2y = 12. Add this to the second equation to get 10x = 30, so x = 3 and y = -3.
In this problem, given the focus at (2,4) and directrix at y = 8. then it is implied that the parabola is facing downwards. The vertex hence is at the middle of the focus and the directrix, hence at (2, 6). The general formula of the parabola is y-k = -4a ( x-h)^2. Substituting, y -6 = -1/8 *(x-2)^2. Answer is A.