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3 years ago

Can someone please help me Factor 4x^2 - 81

Mathematics

2 answers:

Oduvanchick [21]3 years ago

6 0

The answer is (2x-9)(2x+9)

4x^2-81
2^2 x^2-9^2
(2x)^2-9^2
(2x-9)(2x+9)

Vsevolod [243]3 years ago

3 0

Answer:

(2x-9)(2x+9)

Step-by-step explanation:

This is a difference of squares because it can be written as (2x)^2-9^2

The formula for factoring a difference of squares is a^2-b^2=(a-b)(a+b)

So replace a with 2x and b with 9 giving us

4x^2-81=(2x-9)(2x+9)

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1-6. Indicate whether each table or graph represents a proportional

Pie

Answer:

Step-by-step explanation:

Proportional relationship means,

x ∝ y

x = ky

$\frac{x}{y}=k$ where 'k' is the proportionality constant.

From table (1),

$\frac{1}{5}=\frac{2}{9}\neq \text{Constant}$

Therefore, relationship is not proportional.

From table (2),

$\frac{1}{6}=\frac{3}{18}=\text{constant}$

True.

So the relationship will be proportional.

From table (3),

$\frac{\text{hours}}{\text{Miles}}= \frac{2}{110}=\frac{5}{175}=\frac{1}{55}$

Which is constant.

Therefore, relationship will be proportional.

From table (4),

$\frac{\text{Hours}}{\text{Paid}}=\frac{3}{29.25}=\frac{5}{48.75}=0.103$

Which is constant for every term.

Therefore, relationship will be proportional.

7 0

2 years ago

Can someone please help me with this

Ne4ueva [31]

Step-by-step explanation:

Therefore, 55+40+z=180

z=180-95

z=85

To get y,

z+y=180

85+y=180

y=95

5 0

3 years ago

I'm not sure if it's the correct answer

sammy [17]

Answer:

I just looked it up and that is correct!

5 0

2 years ago

29x-7y=-17 solve for x

Serhud [2]

Answer:

$x= -\frac{17}{29} +\frac{7y}{29}$

Step-by-step explanation:

$29x-7y=-17$

$x= -7y/29 + -17/29$ Divide every number by x except

3 0

3 years ago

I need some help, please. : ) <br><br> 25 points. :D

morpeh [17]

X=4 and y= -3 Hope it helps

5 0

1 year ago