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MA_775_DIABLO [31]
3 years ago
5

The line of symmetry for the quadratic equation y = ax2 - 2x - 3 is x = 1. What is the value of "a"?

Mathematics
2 answers:
timama [110]3 years ago
6 0
Y = a(x - h)² + k • (h, k) is the vertex • x = h is line of symmetry so y = ax² - 2x - 3 y/a = x² - 2/ax - 3/a y/a + 3/a = x² - 2/ax y/a + 4/a= x² - 2/ax + (-1/a)² ← completing the square y/a + 4/a= (x - 1/a)² y/a = (x - 1/a)² - 4/a y = a(x - 1/a)² - 4 so since you've been given h = 1 then 1/a = 1 and so a = 1 
kakasveta [241]3 years ago
6 0

Answer:

value of a is 1.

Step-by-step explanation:

A quadratic equation y=ax^2+bx+c  ....[1]  where a, b and c are the coefficient.

then the axis of symmetry is given by:

x = -\frac{b}{2a}             .....[2]

As per the statement:

The line of symmetry for the quadratic equation y = ax^2-2x -3  is x = 1.

On comparing given quadratic equation with [1] we have;

b = -2

then;

Substitute x = 1 in [2] we have;

1= -\frac{-2}{2a}

Simplify:

1 = \frac{1}{a}

⇒a = 1

Therefore, the value of a is 1.

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Write 45/72 in the simplest form
Oliga [24]
Hi! 

In my opinion, the easiest way to solve a problem like this is to find the greatest common factor (GCF) of the numerator and denominator and then divide both numbers by the GCF. 

So first we need to find the factors of 45 and 72 and find the factor that has the most value that the two numbers both have. 

45: 1, 3, 5, 9, 15, and 45

72: 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72

It looks like the GCF is 9. Now we have to divide 45 and 72 by 9. 

45 ÷ 9 = 5

72 ÷ 9 = 8

So the correct answer should be:

\frac{45}{72} =  \frac{5}{8}

Hope this helps :)
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3 years ago
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balandron [24]
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6 0
3 years ago
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WARRIOR [948]

Answer:

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3 years ago
A balloon is rising at a constant speed of 5 ftys. A boy is cycling along a straight road at a speed of 15 ftys. When he passes
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Answer:

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7 0
3 years ago
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baherus [9]
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6 0
3 years ago
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