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3 years ago

An object is launched from a platform.

Mathematics

2 answers:

uysha [10]3 years ago

7 0

Answer:

6seconds

Step-by-step explanation:

Given the height of an object modeled by the expression

h(x)=-5x^2+20x+60

The height of the object on the ground is zero i.e h(x) = 0

On substituting

h(x)=-5x^2+20x+60

0 =-5x^2+20x+60

Multiply through by -1

5x^2-20x- 60 = 0

Divide through by 5

x^2 - 4x - 12 = 0

x^2 - 6x + 2x - 12 = 0

x(x-6)+2(x-6) = 0

(x-6)(x+2) = 0

x - 6 = 0 and x+2 = 0

x = 6 and -2

Since time cannot be negative, hence it takes 6seconds after launch for the object land to on the ground

gregori [183]3 years ago

6 0

Answer:

Step-by-step explanation:

It was correct on Khan.

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use a ratio box to solve this problem. There were 144 books about mammals in the library. If the ratio of books about mammals to

kherson [118]

Answer:

128

Step-by-step explanation:

8 0

2 years ago

The diameter of a cookie is 2 inches. If π = 3.14, what is the area of the cookie, rounded to the nearest tenth?

insens350 [35]

Answer:

3.1 inches

Step-by-step explanation:

Area of the cookie =Pi r^2

Pi = 3.14

Diameter = 2inches

Radius r = diameter/2 = 2/2

= 1

Therefore

Area = 3.14 x 1^2

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3 0

3 years ago

Please someone help me and do not just write anything explain thank you . use the information provided to write the vertex form

notka56 [123]

Ok, so user says that it should be solve for vertex not vertex form
(x,y)
to find the vertex of
y=ax^2+bx+c

the x value of the vertex is -b/2a
the y value is found by plugging in the x value for the vertex back into the original equation and evaluating

y=-2x^2-12x-28
a=-2
b=-12

xvalue of vertex is -(-12)/(2*-2)=12/-4=-3

x value of vertex is -3

plug backin for x
y=-2x^2-12x-28
y=-2(-3)^2-12(-3)-28
y=-2(9)+36-28
y=-18+8
y=-10

yvalue is -10
x value is -3

vertex is (-3,-10)

5 0

3 years ago

PLEASE HELP!! I DO NOT UNDERSTAND THIS ONE BIT. PLEASE RESPOND!

Slav-nsk [51]

Substitute z with 3.
3(4)^3
Cube 4 with 3
3(64)
Multiply 3 and 64
=192

4 0

3 years ago

A science class has 3 girls and 1 boy in the seventh grade and 5 girls and 5 boys in the eighth grade. the teacher randomly sele

brilliants [131]

In the science class,
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and 5 girls and 5 boys (grade 8)
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Which can be simplified into $\frac{3}{7}$ by dividing 2 from the numerator as well as the denominator.

8 0

3 years ago