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3 years ago

What value(s) of x make the equation x2 - 18x + 81 = 0 true?

Mathematics

2 answers:

gayaneshka [121]3 years ago

8 0

X^2 - 18x + 81 = 0
x^2 - 9x - 9x + 81 = 0
x(x - 9) - 9(x - 9) = 0
(x - 9)(x - 9) = 0
(x - 9)^2 = 0
x - 9 = 0
x = 9

ira [324]3 years ago

6 0

Answer:

the answer is 9

Step-by-step explanation:

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Simplify(1\2)^4 1\16 1\8 1\4

tino4ka555 [31]

Step-by-step explanation:

(1\2)^4 x 1\16 x 1\8 x 1\4 [1/2^4=16]

1/16 x 1/512

=>1/2048

5 0

3 years ago

Please help due tonight !

faust18 [17]

The equation: 6r-3=45
6r=48
Answer: r=8

5 0

3 years ago

Solve for x. 5x - 1 = 26 A) x= 27/5 B) 0x=5 C) x= -5

Ber [7]

5x-1= 26

5x-1+1= 26+1

5x= 27

Divide by 5 for 5x and 27

5x/5= 27/5

x= 27/5

Answer is x= 27/5 - A)

4 0

3 years ago

HELP PLZ i need help with this math side i just need b,c,d a =4x+2y=16

tino4ka555 [31]

Answer:

Please check the explanatio.

Step-by-step explanation:

Solving Part b)

We know that the slope-intercept form of the equation line is

$y=mx+b$

where m is the slope and b is the y-intercept

Given the equation

$4x+2y=16$

Re-writing the equation in the slope-intercept form

$4x+2y=16$

$y=-2x+8$

Here, m=-2 and b=8

Thus, the equation in the slope-intercept form will be:

$y=-2x+8$

Solving Part c)

As you sold two pounds of cheddar cheese.

i.e. y=2

substituting y=2 in the slope-intercept form of the line equation

$y=-2x+8$

$2=-2x+8$

Subtract 8 from both sides

$-2x+8-8=2-8$

$-2x=-6$

Divide both sides by -2

$\frac{-2x}{-2}=\frac{-6}{-2}$

$x=3$

You sold 3 pounds of swiss cheese.

Solving Part d)

$y=-2x+8$

putting x=2.5 in the equation

$y=-2x+8$

$2=-2\left(2.5\right)+8$

$2=3$

The sides are not equal

FALSE

Thus, x=2.5 does not make any sense in the context of the problem.

6 0

3 years ago

Makayla and Caroline go to the movie theater and purchase refreshments for their friends. Makayla spends a total of $49.00 on 9

gizmo_the_mogwai [7]

Answer:

Let the cost of each popcorn bag be x and cost of each drink be y

Cost of 9 bags of Popcorn= 9 x

Cost of 8 drinks be = 8 y

Total money spent by Makayla = $ 49

According to Question

9 x + 8 y= 49..................... equation (1)

Similarly , cost of 3 popcorn = 3 x

Cost of 3 drinks= 3 y

Total money spent by Caroline= $ 17.25

According to Question

3 x+ 3 y= $ 17.25...................equation(2)

We can solve above equation by using elimination method

Multiply equation (2) by 3

9 x + 9 y = 51.75..................equation(3)

9 x + 8 y= 49..................... equation (1)

Subtraction equation (1 ) from equation(3)

y = 2.75

put value of y in any equation (2)

we get

3 x + 3 × 2.75 = 17.25

3 x + 8.25 = 17.25

3 x = 17.25 - 8.25

3 x = 9

x = 3

Hence, cost of each popcorn bag $ 3 cost of each popcorn bag is also $ 3 (approx)

5 0

3 years ago