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3 years ago

Solve x^2-8x-9=0 algebrically

Mathematics

1 answer:

SVETLANKA909090 [29]3 years ago

7 0

Answer:

X = 9, -1

Step-by-step explanation:

1, Factor it

(x-9) (x+1) = 0

2. Both of a factor will = 0

x-9 = 0

x+1=0

3. Solve

x=9

x=1

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Given m<br> 11<br> n, find the value of x and y.<br> m<br> (x-1)<br> (y-20)<br> (5x-15)

Olin [163]

Answer:

Step-by-step explanation:

this makes no sense to me

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3 years ago

If y varies directly as x and y = 36 when x = 4,what is the value of y when x=6?

zepelin [54]

Answer:

Step-by-step explanation:

If the two numbers vary directly, we can use a proportion to find the missing value.

36/4 = y/6

4y = 216

Divide by 4

y = 54

Check

36/4 = 54/6

216 = 216 ✅

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2 years ago

Which calculation IS equivalent to 12 x (24 + 17)?

Nitella [24]

The answer is d 41 X 12= 492

Step-by-step explanation:

12 (12 + 17)

12(41)

= 492

5 0

2 years ago

Help it’s slope idk how to do it

Over [174]

a. $\boxed{y-602=\frac{2}{3}(x-3)}$

b. For every month the pine tree grows about 0.67 inches.

c. <em> </em>It represents the height of the tree at the moment Ariel started to record the heights.

<h2>Explanation:</h2>

In this exercise we have that in July Ariel recorded the height of a pine tree and how quickly it was expected to grow in next several months. From the Table, we can get the following points:

$P_{1}(3,602) \\ \\ P_{2}(6,604) \\ \\ P_{3}(q,606) \\ \\ P_{4}(12,608)$

It is obvious that this problem follows a linear equation, so our goal is to find the equation that matches the Table.

The point slope form of the equation of a line is:

$y-y_{1}=m(x-x_{1}) \\ \\ Where: \\ \\ m:Slope \\ \\ (x_{1}, y_{1}):A \ point \ on \ the \ line$

Finding (m):

$Using: \\ \\ P_{1}(x_{1},y_{1}) \rightarrow P_{1}(3,602) \\ \\ P_{2}(x_{2}, y_{2}) \rightarrow P_{2}(6,604) \\ \\ m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}=\frac{604-602}{6-3} \\ \\ m=\frac{2}{3}$

Finally, the equation of the line is:

$(x_{1}, y_{1}) \rightarrow (3,602) \\ \\ \boxed{y-602=\frac{2}{3}(x-3)}$

In this case, we have that:

The x-axis represents the <em>Number of Months </em>the pine tree was expected to grow.
The y-axis represents the <em>Height of the Tree </em>in inches.

Since the slope o a line is:

$Slope=\frac{Change \ in \ y}{Change \ in \ x}=\frac{2}{3}$

Then, this means that<em> every three months the pine tree grows two inches, </em><em>or </em><em>for every month the pine tree grows about 0.67 inches.</em>

The y-intercept can be found setting $x=0$ . So, from our equation:

$y-602=\frac{2}{3}(x-3)} \\ \\ \\ If \ x=0: \\ \\ y-602=\frac{2}{3}(0-3) \\ \\ y-602=-2 \\ \\ Solving \ for \ y: \\ \\ y=602-2 \\ \\ y=600$

So the y-intercept is $y=600$ and<em> represents the height of the tree at the moment Ariel started to record the heights.</em>

<h2>Learn more:</h2>

Slope Intercept form: brainly.com/question/4192440

#LearnWithBrainly

4 0

3 years ago

1. Gavin and Seiji both worked hard over the summer. Together, they earned a total of $425. Gavin earned $25 more than Seiji. Ho

Gre4nikov [31]

Let x = the amount that Seini earned
Then x + 25 = the amount that Gavin
The amount Gavin earned would also = 425 - x (your directions asked you to have 2 equations.)
Together they earned 425:
x + (x + 25) = 425
2x + 25 = 425
2x = 400
Now divide both sides by 2 to find x.

Use all of this data to satisfy the directions.

8 0

3 years ago