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4 years ago

Solve the simultaneous equations 4x+3y=19 5x-4y=47

1 answer:

6 0

4x + 3y = 19 multiply this by 4
5x - 4y = 47 multiply this by 3:-

16x + 12y = 76..............(1)
15x - 12y = 141............(2)

Add (1) + (2);-

31x = 217
x = 7

Now plug = 7 into the first equation:-

4(7) + 3y = 19
3y = 19 - 28 = -9

t = -3

Solution is x = 7, y = -3.

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For the function f(x) = 7/2x-16, what is the difference quotient for all nonzero values of h?

sergey [27]

Answer:

$\frac{f(x + h) - f(x)}{ h} = \frac{7}{2}$

Step-by-step explanation:

Given

$f(x) = \frac{7}{2}x - 16$

Required

The difference quotient for h

The difference quotient is calculated as:

$\frac{f(x + h) - f(x)}{ h}$

Calculate f(x + h)

$f(x) = \frac{7}{2}x - 16$

$f(x+h) = \frac{7}{2}(x+h) - 16$

$f(x+h) = \frac{7}{2}x+ \frac{7}{2}h- 16$

The numerator of $\frac{f(x + h) - f(x)}{ h}$ is:

$f(x + h) - f(x) = \frac{7}{2}x+ \frac{7}{2}h- 16 -(\frac{7}{2}x - 16)$

$f(x + h) - f(x) = \frac{7}{2}x+ \frac{7}{2}h- 16 -\frac{7}{2}x + 16$

Collect like terms

$f(x + h) - f(x) = \frac{7}{2}x -\frac{7}{2}x + \frac{7}{2}h- 16 + 16$

$f(x + h) - f(x) = \frac{7}{2}h$

So, we have:

$\frac{f(x + h) - f(x)}{ h} = \frac{7}{2}h \div h$

Rewrite as:

$\frac{f(x + h) - f(x)}{ h} = \frac{7}{2}h * \frac{1}{h}$

$\frac{f(x + h) - f(x)}{ h} = \frac{7}{2}$

5 0

3 years ago

URGENT DUE BY 1:00 FOR MY FINAL GRADE PLEASE HELP OR I WILL FAIL SEMESTER WILL RATE GOOD THX BLESS YOU!!!!

Lesechka [4]

F(x) = 3x + 11
Is the function used to show this.

when you know this, you are able to do the following:
f(10) = 30 + 11 = $41
That would be the allowance of the 10th week.

The question, however wants the total.

This again, can be done like this:
f(1) + f(2) + f(3) + f(4) + f(5) + f(6) + f(7) + f(8) + f(9) + f(10) = $275 :)
14 + 17 + 20 + 23 + 26 + 29 + 32 + 35 + 38 + 41 = $275

Sure there is a better formula, but i couldnt seem to make it, sorry.

HUGE UPDATE: The sum is $275 not 200..

3 0

4 years ago

Read 2 more answers

How many solutions does -3(2x + 6) = -6x - 18 have

viktelen [127]

Answer: 0=0 The input is an identity or it is true for all values

-3(2x+6)=-6x-18

(-3*2x)+(-3*6)=-6x-18

-6x+-18=-6x-18

0=0

5 0

3 years ago

Find the value of x: x/6 = 16/48 *

allochka39001 [22]

Answer:

x = 2

Step-by-step explanation:

cross multiply!

48x = (16)6

48x = 96

x = 2

4 0

3 years ago

A clothing store marked all of their summer clothing down 50%. A

frozen [14]

The correct answer is 58 yes

6 0

3 years ago