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3 years ago

What is the zero in the quadratic function f(x)= 9x^2-54x-19?

Mathematics

1 answer:

Alex17521 [72]3 years ago

8 0

Answer:

6.33... and 0.333...

Step-by-step explanation:

The quadratic formula is

$x=\frac{-b+\sqrt{b^2-4ac} }{2a}$ .

It is important because while some quadratics are factorable and can be solved not all are. The formula will solve all quadratic equations and can also give both real and imaginary solutions. Using the formula will require less work than finding the factors if factorable. We will substitute a=9, b=-54 and c=-19.

$x=\frac{-b+/-\sqrt{b^2-4ac} }{2a}\\x=\frac{-(-54)+/-\sqrt{(-54)^2-4(9)(-19)} }{2(9)}\\x=\frac{54+/-\sqrt{2916+684} }{18}$

We will now solve for the plus and the minus.

The plus,,,

$x=\frac{54+\sqrt{3600}}{18}\\x=\frac{54+60}{18}\\x=\frac{114}{18}\\x=6.3$

and the minus...

$x=\frac{54-\sqrt{3600}}{18}\\x=\frac{54-60}{18}\\x=\frac{-6}{18}\\x=-0.333...$

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3 years ago

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stealth61 [152]

HI THERE!!!!!

The answer is your question is the second choice 59 in^2.

Here is how you can do it:

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Now you can do the total area:
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3 years ago

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kherson [118]

Answer:

(1/2)x - y = -2

General Formulas and Concepts:

Pre-Alg

Equality Properties

Alg I

Slope-Intercept Form: y = mx + b

m - slope
b - y-intercept

Standard Form: Ax + By = C

Step-by-step explanation:

Step 1: Define equation

Slope-Intercept Form: 2 + (1/2)x = y

Step 2: Find Standard Form

Rewrite: y = (1/2)x + 2
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3 years ago

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Gnoma [55]

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3 years ago

Solving a Quadratic Equation by Completing the Square Solve x2 + 8x = 33 by completing the square. Which is the solution set of

tresset_1 [31]

Divide the coefficient of x by 2 then square the quotient.
Add the result to both sides of the equation.

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Factor the left-hand side.

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Square both sides.

$x + 4 = \sqrt{49}$

Subtract both sides by 4.

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Simplify.

$x = -4$ $± 7$
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So, the answer is {-11, 3}

NOTE: You're probably seeing a strange A in the equations. I tried to fix it, but I couldn't. Sorry about that.

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3 years ago

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