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3 years ago

I really need help asap please

Mathematics

1 answer:

gizmo_the_mogwai [7]3 years ago

5 0

We can use the substitution method to solve this problem.

The second equation is $\sf y=2x$ , so we can plug in 2x for 'y' in the first equation:

$\sf 5x-2y=3$

$\sf 5x-2(2x)=3$

Multiply:

$\sf 5x-4x=3$

Combine like terms:

$\sf x=3$

This is the x-value of our solution, we can plug this into any of the two equations to find the y-value:

$\sf y=2x$

$\sf y=2(3)$

Multiply:

$\sf y=6$

This is the y-value of our solution. So our entire solution is (3, 6).

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ASAP WILL MARK BRAINLYEST <br><br><br>answer these two please!

Trava [24]

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3 0

3 years ago

Which statement describes the inverse of m(x) = x^2 – 17x?

DochEvi [55]

Given:

The function is

$m(x)=x^2-17x$

To find:

The inverse of the given function.

Solution:

We have,

$m(x)=x^2-17x$

Substitute m(x)=y.

$y=x^2-17x$

Interchange x and y.

$x=y^2-17y$

Add square of half of coefficient of y , i.e., $\left(\dfrac{-17}{2}\right)^2$ on both sides,

$x+\left(\dfrac{-17}{2}\right)^2=y^2-17y+\left(\dfrac{-17}{2}\right)^2$

$x+\left(\dfrac{17}{2}\right)^2=y^2-17y+\left(\dfrac{17}{2}\right)^2$

$x+\left(\dfrac{17}{2}\right)^2=\left(y-\dfrac{17}{2}\right)^2$ $[\because (a-b)^2=a^2-2ab+b^2]$

Taking square root on both sides.

$\sqrt{x+\left(\dfrac{17}{2}\right)^2}=y-\dfrac{17}{2}$

Add $\dfrac{17}{2}$ on both sides.

$\sqrt{x+\left(\dfrac{17}{2}\right)^2}+\dfrac{17}{2}=y$

Substitute $y=m^{-1}(x)$ .

$m^{-1}(x)=\sqrt{x+(\dfrac{189}{4}})+\dfrac{17}{2}$

We know that, negative term inside the root is not real number. So,

$x+\left(\dfrac{17}{2}\right)^2\geq 0$

$x\geq -\left(\dfrac{17}{2}\right)^2$

Therefore, the restricted domain is $x\geq -\left(\dfrac{17}{2}\right)^2$ and the inverse function is $m^{-1}(x)=\sqrt{x+(\dfrac{189}{4}})+\dfrac{17}{2}$ .

Hence, option D is correct.

Note: In all the options square of $\dfrac{17}{2}$ is missing in restricted domain.

7 0

3 years ago

Use the identity x^3+y^3+z^3−3xyz=(x+y+z)(x^2+y^2+z^2−xy−yz−zx) to determine the value of the sum of three integers given:

RoseWind [281]

Inserting all the given information into the identity, we have

$684-3(210)=(x+y+z)(110-107)\implies x+y+z=18$

4 0

3 years ago

Warren has 40 coins (all nickels, dimes, and quarters) worth $4.05. He has 7 more nickels than dimes. How many quarters does War

alexdok [17]

7 Quarters

20 nickels

13 dimes

5 0

3 years ago

Joaquin fue al mercado y compro 2,2 kg de papa a S/.1,2 soles el kilo y 3,2 kg de arroz a S/.3,7 soles el kilo, si pagó con un b

nlexa [21]

Responder:

5,52

Explicación paso a paso:

Dado lo siguiente:

Precio por kilo de papa = 1.2

Kg de papa comprada = 2.2kg

Precio por kilo de arroz = 3.7 por kilo

Kg de arroz comprado = 3.2 kg

Valor del boleto emitido para el pago = 20

Precio total de la papa:

Precio * kg comprado

1.2 * 2.2 = 2.64

Precio total del arroz:

Precio * kg comprado

3.7 * 3.2 = 11.84

Cantidad total gastada = (precio total del arroz + precio total de la papa)

2.64 + 11. 84 = 14.48

Cambio pendiente = 20 - 14.48 = 5.52

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3 years ago