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3 years ago

Solve by addition method 3x+y=8 2x-y=7

Mathematics

1 answer:

Vinil7 [7]3 years ago

7 0

Answer:

(3,-1)

Step-by-step explanation:

So we have the system of equations:

$3x+y=8\\2x-y=7$

As directed, add straight down. The y-variable will cancel:

$5x=15$

Now, divide both sides by 5. The left cancels:

$x=3$

So x is 3.

Now, substitute 3 for x in either of the equations:

$3x+y=8$

Substitute 3 for x:

$3(3)+y=8$

Multiply:

$9+y=8$

Subtract 9 from both sides:

$y=-1$

So, our answer is: x=3, y=-1 or (3,-1).

And we are done :)

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Write the equation of a function whose parent function, f(x) = x + 6, is shifted 4 units to the right.

NeTakaya

Answer:

g(x) = x + 2 ⇒ 3rd answer

Step-by-step explanation:

* Lets revise the translation

- If the function f(x) translated horizontally to the right

by h units, then the new function g(x) = f(x - h)

- If the function f(x) translated horizontally to the left

by h units, then the new function g(x) = f(x + h)

* Lets solve the problem

∵ The parent function f(x) = x + 6

∵ f(x) is shifted four units to the right

- The translation of a function by h units to the right change the x in

the function by subtracting h from it

∴ The x in f(x) will change to (x - 4)

∴ The new function = (x - 4) + 6

- Simplify the function

∴ The new function = x + 2

∵ The new function is g(x)

∴ g(x) = x + 2

4 0

3 years ago

Read 2 more answers

Sam saw 2 bottles of ketchup at the store for the same price. One bottle contained 4 pints of ketchup and the other contained 1.

Ilia_Sergeevich [38]

I do believe that it's the bottle with the 4 pints of ketchup. 4 pints is 2 quarts

3 0

3 years ago

Sara had a balance of $350 in her bank account. Her electric bill was $375. After she pays the electric bill, what amount of mon

Alex_Xolod [135]

She should deposit $25.
$375 - $350 = $25

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3 years ago

Find the missing factor 2x^2+15x+7=(2x+1)(?)

Genrish500 [490]

Answer:

? = (x + 7)

Step-by-step explanation:

2x^2 + 15x + 7 = (2x + 1) (?)

1. First you need to figure out what multiplied by 2x will give you 2x^2, which is x.

2. Then you need to find what would give you 15x. In this case because you have the 1 in (2x + 1), you already know that there is going to be an extra x. So, what times 2x gives you 14x? It's 7.

3. Lastly you need to make sure that 1 multiplied with 7 is equal to 7 and combine like terms.

4. Check: (2x + 1) (x + 7) =

2x^2 + 14x + 1x + 7 =

2x^2 + 15x + 7

5 0

3 years ago

The "absorption law" (theorem 2.1.1 in our book) states that p V (p Aq) is logically equivalent to p. Construct a truth table to

Sloan [31]

Answer:

According to the Law of Absorption, these 2 expressions are equivalent:

p ∨ (p ∧ q) = p

Truth Table:

(see the image attached)

Step-by-step explanation:

To construct the Truth Table you can consider the 4 possible combinations of states that p and q could have, that is

1. p=T, q=T

2. p=T, q=F

3. p=F, q=T

4. p=F, q=F

Then you can calculate p ∨ (p ∧ q) = p for each combination

1. T ∨ (T ∧ T) = T

2. T ∨ (T ∧ F) = T

3. F ∨ (F ∧ T) = F

4. F ∨ (F ∧ F) = F

You can see that the previous values are the same states that p has, you can also see it in the table attached.

5 0

3 years ago