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3 years ago

Solve 9x2 + 6 = 12x

Mathematics

1 answer:

Oksana_A [137]3 years ago

7 0

Step-by-step explanation:

9x² + 6 = 12x

3x² + 2 = 4x

3x² − 4x + 2 = 0

Use quadratic formula.

x = [ -b ± √(b² − 4ac) ] / 2a

x = [ -(-4) ± √((-4)² − 4(3)(2)) ] / 2(3)

x = [ 4 ± √(16 − 24) ] / 6

x = [ 4 ± √(-8) ] / 6

x = (4 ± 2i√2) / 6

x = (2 ± i√2) / 3

You might be interested in

Solve the following 3 × 3 system. Enter the coordinates of the solution below.

ICE Princess25 [194]

Step-by-step explanation:

2x - 3y - 2z = 4

[2] x + 3y + 2z = -7

[3] -4x - 4y - 2z = 10

Solve by Substitution :

// Solve equation [2] for the variable x

[2] x = -3y - 2z - 7

// Plug this in for variable x in equation [1]

[1] 2•(-3y-2z-7) - 3y - 2z = 4

[1] - 9y - 6z = 18

// Plug this in for variable x in equation [3]

[3] -4•(-3y-2z-7) - 4y - 2z = 10

[3] 8y + 6z = -18

// Solve equation [3] for the variable z

[3] 6z = -8y - 18

[3] z = -4y/3 - 3

// Plug this in for variable z in equation [1]

[1] - 9y - 6•(-4y/3-3) = 18

[1] - y = 0

// Solve equation [1] for the variable y

[1] y = 0

// By now we know this much :

x = -3y-2z-7

y = 0

z = -4y/3-3

// Use the y value to solve for z

z = -(4/3)(0)-3 = -3

// Use the y and z values to solve for x

x = -3(0)-2(-3)-7 = -1

Solution :

{x,y,z} = {-1,0,-3}

6 0

3 years ago

Martin works at bluebell ice cream parlor.He earns $87.50 for every 7 hours of work.Based on this information how much money wou

faust18 [17]

Martin will earn $350 for 28 hours of work.

Step-by-step explanation:

Given,

Amount earned in 7 hours = $87.50

Ratio of time to amount earned = 7:87.50

Let,

x be the amount earned in 28 hours.

Ratio of time to amount earned = 28:x

Using proportion;

Ratio of time to amount earned :: Ratio of time to amount earned

$7:87.50::28:x\\$

Product of mean = Product of extreme

$7*x=87.50*28\\7x=2450$

Dividing both sides by 7

$\frac{7x}{7}=\frac{2450}{7}\\x=350$

Martin will earn $350 for 28 hours of work.

Keywords: ratio, proportion

Learn more about proportion at:

#LearnwithBrainly

4 0

3 years ago

Please help lolol.....

miskamm [114]

Answer:

Step-by-step explanation:

cuz

4 0

3 years ago

Read 2 more answers

Laura and Martin obtain a 30-year, $180,000 conventional mortgage at 10.0% on a house selling for $210,000. Their monthly mortga

Westkost [7]

Answer:

total payment = $563,760

Interest = $383,760

Principal part = $66

Step-by-step explanation:

(a) total payment:

n = 30 years = 360 months

monthly payment = $1,566

Total payment = $1,566 * 360 months = $563,760

(b) interest:

Total payment = $563,760

Principal = $180,000

Total payment = Principal + Interest

Interest = Total payment - Principal

Interest = $563,760 - $180,000 = $383,760

(c) part of first payment applied to the principal:

First payment = $1,566

Principal = $180,000

Interest rate = 10% yearly = 10% / 12 = 0.8333% = 0.008333 monthly

Monthly interest = Principal * Interest rate = $180,000 * 0.008333 = $1,500

Principal part = $1,566 - $1,500 = $66

Hope this helps!

4 0

3 years ago

The product of 4 and a number f decreased by 2 is 15

Debora [2.8K]

Answer: The number is: "2 " .

__________________________________________

Step-by-step explanation:

__________________________________________

Write the expression; which is an equation, as follows:

__________________________________________

" 4x − 12 = 2(-x) " ; in which "x" represents "the number for which we shall solve" .

___________________________________________

Note:

If the "number" = "x" ; the "opposite of the number" = " -x " ;

___________________________________________

Rewrite as: " 4x − 12 = -2x " ;

_____________________________________________

→ Add "12" ; & add "2x" ; to EACH SIDE of the equation:

4x − 12 + 12 + 2x = -2x + 12 + 2x ;

to get: 6x = 12 ;

____________________________________________________

Now, divide each side of the equation by "6" ;

to isolate "x" on one side of the equation; & to solve for "x" ;

____________________________________________________

6x / 6 = 12 / 6 ;

to get: x = 2 .

____________________________________________________

Answer: The number is: "2 " .

____________________________________________________

Let us check our answer, by plugging in "2" for "x" in our original equation:

_____________________________________________________

→ " 4x − 12 = 2(-x) " ;

Let us plug in "2" for "x" ; to see if the equation holds true; that is; if both side of the equation are equal; when "x = 2" ;

→ " 4(2) − 12 = ? 2(-2) ??

→ 8 − 12 = ? -4 ? ;

→ -4 = ? -4 ?? Yes!

__________________________________________________

7 0

3 years ago

Read 2 more answers