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3 years ago

9y-7=56 y=?: show work

Mathematics

2 answers:

enyata [817]3 years ago

6 0

Answer:

53.12

Step-by-step explanation:

1234567890

Lilit [14]3 years ago

6 0

Answer:

y = 7

Step-by-step explanation:

9y - 7 = 56

+7 +7

9y = 63

/9 /9

y = 7

(/9 = divided by 9)

check : 9 x 7 = 63 ( 63 - 7 = 56) correct!

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If r is the midpoint of AB and AR=14, then AB=______

skelet666 [1.2K]

Answer:

Step-by-step explanation:

The midpoint is halfway, so if half the length is 14 then the full length is 28 (14 × 2 = 28)

Hope this helps!

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2 years ago

Felix’s Feed Mill sells chicken feed for $8.00 per bag. This price is no longer high enough to create a profit. Felix decides to

Soloha48 [4]

Answer:

Step-by-step explanation:

essentially the plan that increases the price the most per week reaches the goal of $12 fastest.

plan A is $0.10 per week.

plan B it is not clear, if it means 10% of the original price every week, or every week 10% of the price of the previous week. I assume the first and simplest.

that means 10% of $8 = $0.80 per week.

plan C : the same amount every week until reaching $12. we need to increase in total by $4 (from $8 to $12). to reach these $4 in 8 weeks, we need to increase the price every week by 4/8 = $0.50.

plan D : $0.25 per week.

so, the plan with the highest increase every week and therefore the fastest one reaching $12 is plan B.

8 0

1 year ago

Solve the equation for a w=7a+4b

Murljashka [212]

W=7a+4b
w-4b = 7a
$a= \frac{w-4b}{7}$

6 0

2 years ago

Help i dont understand how to complete this

Luda [366]

Answer: Josh = 19.8 hours, Danny = 10.8 hours

Step-by-step explanation:

$Josh: \dfrac{1}{x+9}\\\\\\Danny: \dfrac{1}{x}\\\\\\Together: \dfrac{1}{7}\\\\\\Josh\quad + \quad Danny\quad =\quad Together\\\dfrac{1}{x+9}\quad +\qquad \dfrac{1}{x}\qquad = \qquad \dfrac{1}{7}\\\\\\\underline{\text{Clear the denominator by multiplying by the LCM: (x+9)(x)(7)}}\\\\7(x) + 7(x+9)=x(x+9)\\7x + 7x + 63 = x^2+9x\\14x+63=x^2+9x\\0=x^2-5x-63\\\\\\\underline{\text{Use the quadratic formula to solve for x: }}x=\dfrac{-b\pm \sqrt{b^2-4ac}}{2a}$

$x=\dfrac{-(-5)\pm \sqrt{(-5)^2-4(1)(-63)}}{2(1)}\\\\\\.\quad =\dfrac{5\pm\sqrt{25+252}}{2}\\\\\\.\quad =\dfrac{5\pm\sqrt{277}}{2}\\\\\\.\quad =\dfrac{5\pm 16.6}{2}\\\\\\x =\dfrac{5+16.6}{2}\qquad x=\dfrac{5-16.6}{2}\\\\\\x=\dfrac{21.6}{2}\qquad \qquad x=\dfrac{-11.6}{2}\\\\\\x=10.8 \qquad \qquad x=-5.8$

Since time cannot be negative, x=-5.8 is an extraneous solution (not valid) so x = 10.8

Josh: x + 9 --> 10.8 + 9 = 19.8

Danny: x --> 10.8

****************************************************************************************

2a) k = 9.45 & 0.55

2b) x = 3/2

2c) x = 2/3 (x = -1 is an extraneous solution so is not valid)

2d) No Solution (x = 1 is an extraneous solution so is not valid)

Here is the work for 2a. Follow this format for b, c, & d

$\dfrac{3}{k^2-8x+12}=\dfrac{k}{k-2}-\dfrac{4}{k-6}\\\\\text{Since the denominator cannot equal zero, then } k \neq2\ and\ k\neq6\\\text{If either of the solutions are 2 or 6, then that solution needs to be crossed out}\\\\\underline{\text{Clear the denominator by multiplying by the LCM: (k-2)(k-6)}}\\\\3 = k(k-6)-4(k-2)\\3=k^2-6k-4k+8\\0=k^2-10k+5\\\\\\\underline{\text{Use the quadratic formula to solve for k}}$

$x=\dfrac{-(-10)\pm \sqrt{(-10)^2-4(1)(5)}}{2(1)}\\\\\\.\quad =\dfrac{10\pm\sqrt{100-20}}{2}\\\\\\.\quad =\dfrac{10\pm\sqrt{80}}{2}\\\\\\.\quad =\dfrac{10\pm8.9}{2}\\\\\\x=\dfrac{10+8.9}{2}\qquad x=\dfrac{10-8.9}{2}\\\\\\x=\dfrac{18.9}{2}\qquad x=\dfrac{1.1}{2}\\\\\\x=9.45\qquad x=0.55\\\\\\\text{Both answers are valid!}$

8 0

3 years ago

4x+5y=-13;5x-2y=-8 solve elimination method Step by step

goldfiish [28.3K]

4x + 5y = -13
2(4x + 5y) = 2(-13)
8x + 10y = -26 (equation 1)

5x - 2y = -8
5(5x - 2y) = 5(-8)
25x - 10y = -40 (equation 2)

equation 1 + equation 2,
(8x + 10y) + (25x - 10y) = (-26) + (-40)
8x + 10y + 25x - 10y = -26 + -40
33x = -66
x = -2

substitute x = -2 into equation 1,
8x + 10y = -26
8(-2) + 10y = -26
-16 + 10y = -26
10y = -10
y = -1

The values of x and y are -2 and -1 respectively.

8 0

3 years ago