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soldier1979 [14.2K]
4 years ago
14

Without solving the equation, determine the nature of the roots of x2 - 2 x - 8 = 0.

Mathematics
1 answer:
ad-work [718]4 years ago
3 0
Evaluate using the discriminant (the part of the quadratic equation under the square root sign) b²-4ac
In your equation, a=1, b=(-2), and c=(-8)...substitute their values into the discriminant:
(-2)²-4(1)(-8)
4+32 = 36

The value is positive, therefore the equation has two real roots.
It's a perfect square (√36=6) so the roots are rational
Answer: two real, rational roots

(If the result was a negative number, the system would have two irrational roots. If the result was zero, the system would have a <em>double root </em>(one value repeated twice - when graphed, the vertex of the parabola falls on the x-axis)∨<em />
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What is the answer to <br> m/5 =10?
nata0808 [166]

Answer:

m/5=10

  • Step-by-step explanation: m/5=10
  • 5*m/5=10*5
  • m=50

5 0
3 years ago
Read 2 more answers
PLEASE HELP. WILL MARK BRAINLIEST.
Alina [70]

Answer:

y = x² + 6x + 8

Step-by-step explanation:

The zeros ( x- intercepts ) of the graph are x = - 4 and x = - 2, thus

the factors are (x + 4) and (x + 2) and the function is the product of the factors.

y = a(x + 4)(x + 2) ← a is a multiplier

To find a substitute (0, 8 ) the y- intercept into the equation

8 = a(0 + 4)(0 + 2) = a(4)(2) = 8a ( divide both sides by 8 )

a = 1, thus

y = (x + 4)(x + 2) ← expand using FOIL

  = x² + 6x + 8

6 0
3 years ago
Can someone please help me find the domain, range, intercepts, and asymptotes pf this function?
marishachu [46]
1) given function

y = - 2 ^ ( -x + 2) + 1

2) domain: domain is the set of the x-values for which the function is defined.

The exponential function is defined for all the real numbers, so the domain of the given function is all the real numbers.

3) x-intercept => y = 0

=> y = - 2 ^ ( -x + 2) + 1 = 0 => 2^ ( -x + 2) = 1

=> - x + 2 = 0 => x = 2

The x-intercept is x = 0

4) y-intercept => x = 0

=> y = - 2 ^ ( -x + 2) + 1= - 2 ^ ( 0 + 2)  1 = - (2)^(2) + 1 =- 4 + 1 = - 3

=> The y-intercept is - 3

5) limit when x -> negative infinite

Lim f(x) when x -> ∞ = - ∞

6) limit when x -> infinite

Lim f(x) when x - > infinite = 1

=> asymptote = y = 1

7) range is the set of values of the fucntion: y

Given that the function is strictly decreasing from -∞ to ∞, the range is from - ∞ to less than 1

Range (-∞,1)


3 0
3 years ago
True or false (Picture provided)
Naya [18.7K]
<h2>Hello!</h2>

The answer is: True.

<h2>Why?</h2>

A counterexample is a way that we can prove that something is not true about a mathematical equation or expression, it's also considered as an exception to a rule.

So:

sec^{2}x-1=\frac{cosx}{cscx}\\\\tg^{2}x=\frac{cosx}{\frac{1}{sinx}}\\\\\frac{1-cos2x}{1+cos2x}=cosxsinx

Then, evaluating we have:

\frac{1-cos(2*45)}{1+cos(2*45)}=cos(45)*sin(45)\\\\\frac{1-0}{1+0}=\frac{\sqrt{2} }{2}*\frac{\sqrt{2}}{2}\\\\1=\frac{(\sqrt{2})^{2} }{4}\\\\1=\frac{2}{4}\\\\1=\frac{1}{2}

Hence, we can see that the equation is not fulfilled, so, 45° is a counterexample for sec^{2}x-1=\frac{cosx}{cscx} and the answer is true.

Have a nice day!

3 0
3 years ago
A pool has length 30 yards width 10 yards and depth .3 yards find the surface area of the pool in the volume of water it holds
puteri [66]
You find volume by multiplying length times width so the answer would be 300
3 0
3 years ago
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