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3 years ago

I need help solving x^2-2=7 by factoring

Mathematics

1 answer:

bonufazy [111]3 years ago

4 0

x^2-2=7

Subtract 7 from both sides

x^2-2-7=7-7

x^2-9=0

x^2-3^2=0

Using a^2-b^2=(a+b)(a-b)

Where a=x and b=3

(x-3)(x+3)

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Write the equation of a line in slope-intercept form that is perpendicular to the line y = 3/5 = 1 and passes through the point

4vir4ik [10]

The slope of the line $y=\frac{3}{5} x-1$ is $m=\frac{3}{5}$ .

The line perpendicular to the above line has slope $-\frac{1}{m} =-\frac{5}{3}$

Its equation is $y=-\frac{5}{3} x+c$ . Since this line passes through, $(-9,4)$ ,

$4=-\frac{5}{3} )(-9)+c\\ c=-11$

Thus the equation of the line in slope intercept form is $y=-\frac{5}{3} x-11$

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3 years ago

4. Which of the two figures below has the lesser volume?

elena55 [62]

Answer:

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7 0

3 years ago

Can someone pls tell me if this is right? if its not then what is the right answer?

noname [10]

Answer:

It's right :)

Explanation:

Dilation along the x-axis = (-7-1)/(-1-1) = 2/8 = 1/4
Dilation along the y-axis = (-7-1)/(-1-1) = 2/8 = 1/4

Thus, the overall dilation is 1/4

3 0

2 years ago

Read 2 more answers

Which statement is not true about the pattern shown 2/3 , 4/6, 8/12, 16/24 , ...

natta225 [31]

They are multiplying by two .

8 0

3 years ago

The chemistry class was making 300 gallons of 30% isopropyl alcohol. They mixed 12% with 42%. How much of each did they use?

alexgriva [62]

Answer:

The chemistry class mixed 120 gallons of 12% isopropyl alcohol and 180 gallons of 42% isopropyl alcohol.

Step-by-step explanation:

1. Let's review the information given to us to answer the question correctly:

Amount of isopropyl alcohol made by the chemistry class = 300 of 30%

Amount of 12% isopropyl alcohol mixed by the chemistry class = x

Amount of 42% isopropyl alcohol mixed by the chemistry class = 300 - x

2. How much of each did they use?

Let's write our equation to solve for x, this way:

30% = 0.3, 12% = 0.12, 42% = 0.42

0.12x + 0.42 (300 - x) = 0.3 * 300

0.12x + 126 - 0.42x = 90

-0.3x = 90 - 126

-0.3x = -36

x = -36/-0.3

x = 120 ⇒ 300 - x = 180

Let's prove x = 120 is correct

0.12x + 0.42 (300 - x) = 0.3 * 300

0.12 * 120 + 0.42 (300 - 120) = 0.3 * 300

14.4 + 75.6 = 90

90 = 90

We proved x = 120 is correct

5 0

3 years ago