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3 years ago

Find the product: (x+9)(x-9) a 18 b. -81 C. - 18 d. x-64

Mathematics

2 answers:

Lilit [14]3 years ago

5 0

Answer:

x^2 -81

Step-by-step explanation:

(x+9)(x-9)

FOIL

first x*x = x^2

outer -9x

inner 9x

last -9*9 = -81

Add them together

x^2 -9x+9x -81

Combine like terms

x^2 -81

olga nikolaevna [1]3 years ago

4 0

Answer: B

Step-by-step explanation:

Simply using (a-b)(a+b)=a^2-b^2.

Evaluate the power (9^2).

x^2 - 81

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System A has ONE real solution

System B has NO real solutions

System C has ONE real solution

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Decide which of the two points lies on the graph of the line 2x+y=10 A.(4,3) B.(-4,18)

allochka39001 [22]

Answer:

Step-by-step explanation:

when you substitute 4 in x and 3 in y, your result are 11 no 10

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3 years ago

The figure shows a cylinder of diameter 12cm and height = 15cm. A hole in the shape of cone is bored into one of its end. If the

Lisa [10]

Answer:

$\bold{495\pi} \approx \bold{1555.088 cm^3}$

Step-by-step explanation:

There was no figure but the question is clear

Volume of a cylinder is given by the formula $\bold{\pi r^2h}\\$

where r is radius of base of cylinder, h is the height

Volume of a cone is given by $\bold{\frac{1}{3} \pi r^2 h}$

where r is the radius of base of cone, h is the height

The radius of the cylinder = $\frac{1}{2}$ (diameter) = $\frac{1}{2}$ (12) = 6cm

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Volume of cylinder $V_{cyl} = \pi (6)^2 15 = \pi (36)15 = \bold{540\pi}$

Radius of cone = $\frac{1}{2}$ (radius of cylinder) = $\frac{1}{2}$ (6) = 3 cm

Height of cone same as height of cylinder = 15cm

Volume of cone, $V_{cone} = \frac{1}{3}\pi r^2 h = \frac{1}{3}\pi (3)^2 15 = \frac{1}{3}(9)15\pi = \bold{45\pi}\\$

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1 year ago

What is 34-5x6? Help pls thx

azamat

Answer:

Step-by-step explanation:

Order of operations multiplication then subtraction so 5*6=30

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2 years ago

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Divide 32 on both sides.

x = 2400/32

x = 75

75 percent of 32 is 24

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2 years ago

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