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3 years ago

Which of the following equations is quadratic? x(x2 + 1) = 0 5(4x + 2) = 3 (x + 3)(x + 4) = 5

1 answer:

6 0

An equation is quadratic if the highest power of the variable in it is 2.

$1. \\
x(x^2+1)=0 \\
x^3+x=0 \\
\hbox{the highest power: 3} \\
\hbox{not quadratic} \\ \\
2. \\
5(4x+2)=3 \\
20x+10=3 \\
20x+7=0 \\
\hbox{the highest power: 1} \\
\hbox{not quadratic} \\ \\
3. \\
(x+3)(x+4)=5 \\
x^2+4x+3x+12=5 \\
x^2+7x+7=0 \\
\hbox{the highest power: 2} \\
\hbox{quadratic}$

(x+3)(x+4)=5 is a quadratic equation.

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The perimeter of a triangular sail is 44 feet. One side of the sail measures 18 feet and the second side measures 11 feet. What

Fantom [35]

Answer: The length of third side is 15.

Step-by-step explanation:

Alright, lets get started.

Please refer the diagram I have attached.

The perimeter of given triangle is 44.

One side, suppose a is 18.

Second side, suppose b is 11.

Suppose, third side is c.

So the perimeter will be :

$18+11+c=44$

$29+c=44$

Subtracting 29 in both sides

$29+c-29=44-29$

$c=15$

Hence the length of third side is 15. Answer

Hope it will help :)

6 0

3 years ago

The length of a rectangle is three times the width. The sum of the length and the width is 24 inches. What is the length of the

nikitadnepr [17]

Answer:

Length: 18 inches

Width: 6 inches

Step-by-step explanation:

l+w=24

l=3w w=1w

3w+w=24

w=6

Length: 3*6=18 inches

Width: 6 inches

3 0

2 years ago

QveST [7]

Answer: 9 L

Step-by-step explanation:

Given

The dimension of the rectangular container is $40\times 30\times 25\ cm^3$

It is filled with $\frac{3}{5}$ of the height

Water present in the container

$\Rightarrow 40\times 30\times 25\times \dfrac{3}{5}\\\\\Rightarrow 18000\ cm^3$

Also, $1\ L=1000\ cm^3$

$\therefore 18,000\ cm^3=18\ L$

Now, half of the water is poured out

So, half is left

$\Rightarrow \dfrac{18}{2}=9\ L$

Thus, 9 L of water is left in the container

5 0

3 years ago

Ainsley lives in a town 360 miles directly north of Orlando, and one Saturday, she takes the train from her town to the city. he

iragen [17]

By definition we have to:
d = v * t
where,
d: distance
v: speed
t: time
We have then that the speed is:
(360-210) = v * 2.5
Clearing we have:
v = (360-210) /2.5
v = 60 mph
We now write the generic equation of distance:
d (x) = 60x
Where,
x: time
Answer:
an equation that represents (x), the distance Ainsley is from Orlando after x hours is:
d (x) = 60x

5 0

4 years ago

To obtain information on the corrosion-resistance properties of a certain type of steel conduit, 45 specimens are buried in soil

Ugo [173]

Answer:

Step-by-step explanation:

Set up hypotheses as

$H_0: x bar = 50\\H_a: x bar$

(Left tailed test at 5% level)

Sample mean = 53.4

Sample std dev s = 4.4

Sample std error = 4.4/sqrt 50 = 0.6222

Mean diff = 3.4

Test statistic = Mean diff/std error = 0.5464

(t test only can be used as population sigma is not known)

df = 50-1 =49

p value = 0.2939

Since p>0.05 we accept null hypothesis

Specification has not been met.

6 0

4 years ago