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2 years ago

Solve: 2x2-x = 21 {-7/2,3} {-3, 7/2}

Mathematics

1 answer:

Sergio039 [100]2 years ago

4 0

Answer:

The answer is (-3,7/2)

Step-by-step explanation:

$2 {x}^{2} - x - 21 = 0 \\ (2x - 7)(x + 3) = 0 \\ 2x - 7 = 0 \: \: \: or \: \: x + 3 = 0 \\ x = \frac{7}{2} \: \: and \: x = - 3$

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Find the length of the third side. If necessary, write in simplest radical form.

Angelina_Jolie [31]

Answer:

the length of the missing side is 2

Step-by-step explanation:

Use a^2 + b^2 = c^2

a = 4

b = ?

c = 2sqrt5

4^2 + b^2 = (2sqrt5)^2

16 + b^2 = 20

subtract 16 from both sides

b^2 = 4

take the sqrt of both sides

b = 2

3 0

1 year ago

Read 2 more answers

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Oliga [24]

Answer:

The class 35 - 40 has maximum frequency. So, it is the modal class.

From the given data,

$\sf \:\:\:\:\:\:\:\:\:\:x_{k}=35$
$\sf \:\:\:\:\:\:\:\:\:\:f_{k}=50$
$\sf \:\:\:\:\:\:\:\:\:\:f_{k-1}=34$
$\sf \:\:\:\:\:\:\:\:\:\:f_{k+1}=42$
$\sf \:\:\:\:\:\:\:\:\:\:h=5$

${\bf \:\: {By\:using\:the\: formula}} \\ \\$

$\:\dag\:{\small{\underline{\boxed{\sf {Mode,\:M_{o} =\sf\red{x_k + {\bigg(h \times \: \dfrac{ ( f_k - f_{k-1})}{ (2f_k - f_{k - 1} - f_{k +1})}\bigg)}}}}}}} \\ \\$

$\sf \:\:\:\:\:\:\:\:\:= 35+ {\bigg(5 \times \dfrac{(50 - 34)}{ ( 2 \times 50 - 34 - 42)}\bigg)} \\ \\$

$\sf \:\:\:\:\:\:\:\:\:\:\:\:\:\:\:= 35 +{\bigg(5 \times \dfrac{16}{24}\bigg)} \\ \\$

$\sf \:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:= {\bigg(35+\dfrac{10}{3}\bigg)} \\ \\$

$\sf \:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:(35 + 3.33) =.38.33 \\ \\$

$\:\:\sf {Hence,}\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\ \large{\underline{\mathcal{\gray{ mode\:=\:38.33}}}} \\ \\$

${\large{\frak{\pmb{\underline{Additional\: information }}}}}$

MODE

Most precisely, mode is that value of the variable at which the concentration of the data is maximum.

MODAL CLASS

In a frequency distribution the class having maximum frequency is called the modal class.

${\bf{\underline{Formula\:for\: calculating\:mode:}}} \\$

${\underline{\boxed{\sf {Mode,\:M_{o} =\sf\red{x_k + {\bigg(h \times \: \dfrac{ ( f_k - f_{k-1})}{ (2f_k - f_{k - 1} - f_{k +1})}\bigg)}}}}}} \\ \\$

Where,

$\sf \small\pink{ \bigstar} \: x_{k}= lower\:limit\:of\:the\:modal\:class\:interval.$

$\small \blue{ \bigstar}$ $\sf \: f_{k}=frequency\:of\:the\:modal\:class$

$\sf \small\orange{ \bigstar}\: f_{k-1}=frequency\:of\:the\:class\: preceding\:the\;modal\:class$

$\sf \small\green{ \bigstar}\: f_{k+1}=frequency\:of\:the\:class\: succeeding\:the\;modal\:class$

$\small \purple{ \bigstar}$ $\sf \: h= width \:of\:the\:class\:interval$

7 0

2 years ago

Factor the trinomial below.

arsen [322]

Option C is your answer.

9x² + 6x + 1
9x² + 3x + 3x + 1
3x(3x + 1) + 1(3x + 1)

(3x + 1)(3x + 1)

5 0

2 years ago

What is the distance between the points (-6,5) and (8,-2) on a coordinate plane?

Naddik [55]

Distance Formula: $D=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2$

Apply the points: $D=\sqrt{(8-(-6))^2+((-2)-5)^2$

Solve: $D=\sqrt{(8-(-6))^2+((-2)-5)^2}\\D=\sqrt{14^2+(-7)^2}\\D=\sqrt{169+49}\\D=\sqrt{218}$

Since the square root of 218 cannot be simplified, the answer is

$D=\sqrt{218}$

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7 0

2 years ago

A rectangular room is 6.8 meters longer than it is wide, and perimeter is 29.6 meters. Find the dimensions of the room.

GuDViN [60]

Answer:

dimensions = 10.8 X 4

Step-by-step explanation:

Breadth/ width of room = x

Length of room = 6.8 + x

perimeter = 2 ( L + B )

29.6 = 2 ( 6.8 + x + x )

29.6/2 = 6.8 + 2x

14.8 - 6.8 = 2x

8 = 2x

8/2=x

4=x

Length of room = 6.8 + x = 6.8 + 4 = 10.8 m

Breadth/ width of room = x = 4m

8 0

2 years ago

Solve: 2x2-x = 21 {-7/2,3} {-3, 7/2}​

Solve: 2x2-x = 21 {-7/2,3} {-3, 7/2}