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2 years ago

Which equation combines with the given equation to form a system of equations with the solution x = 3 and y = 9? x + 2y = 21

2 answers:

max2010maxim [7]2 years ago

6 0

Yes. x=3 and y =9 are the solutions.
Because if you change x=3 and y =9 ,you will have
3+2* 9 =21
3+18 =21
21 =21 (true)

Gekata [30.6K]2 years ago

4 0

Answer:

x + 2y = 21

Step-by-step explanation:

Even other options have not been given in this question, But we will prove that equation that combines to form a system of equations is x + 2y = 21

For this we will prove this equation true for x = 3 and y = 9

x + 2y = 21

3 + 2×9 = 21

3 + 18 = 21

21 = 21

Therefore, equation x + 2y = 21 combines to form a system of equations.

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If mc022-1.j pg and mc022-2.j pg, what is the value of (f – g)(144)? –84 –60 0 48

Mashutka [201]

Answer:

Step-by-step explanation:

f(x) = √(x) + 12

g(x) = 2√(x)

(f-g)(x) = √(x) + 12 - 2√(x)

(f-g)(x) = 12 - √(x)

if x = 144

(f-g)(144) = 12 - √(144) = 12 - 12 = 0

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2 years ago

Read 2 more answers

Sten sat on a bench and read a book while Manu was at soccer practice. He read for 35 minutes and stopped at 6:10 p.m.

Dahasolnce [82]

Answer:

5:35

Step-by-step explanation:

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2 years ago

If r=[x,y,z] and r0=[x0,y0,z0], describe the set of all points (x,y,z) such that Ir-r0I =1.

sdas [7]

Answer:

The points (x,y,z) that respond to Ir-r0I =1, are all that describes the form $(x-x_0)^2+(y-y_0)^2+(z-z_0)^2=1$ with:

-1+x₀<x<1+x₀

-1+y₀<y<1+y₀

-1+z₀<z<1+z₀

Step-by-step explanation:

All points required in this problem came from applying the definition of modulus of a vector:

Ir-r0I =1.

$|(x,y,z)-(x_{0},y_{0},z_{0})|=|(x-x_{0},y-y_{0},z-z_{0})|=\sqrt{(x-x_{0})^2+(y-y_{0})^2+(z-z_{0})^2}=1\\(x-x_{0})^2+(y-y_{0})^2+(z-z_{0})^2=1^2=1$

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2 years ago

The graph of which function passes through (0,3) and has an amplitude of 3? f (x) = sine (x) + 3 f (x) = cosine (x) + 3 f (x) =

Cloud [144]

Answer:

$f(x)=3*cosine(x)$

Step-by-step explanation:

We are looking for a trigonometric function which contains the point (0, 3), and has an amplitude of 3.

We know that for a sine function $f(x)=sin(x)$ , $f(0)= 0$ ; therefore the function we a looking for cannot be a sine function because it is zero at $x=0$ .

However, the cosine function $f(x)=cos(x)$ gives non-zero value at $x=0:$

$f(0)=cos(0)=1$

therefore, a cosine function can be our function.

Now, cosine function with amplitude $a$ has the form

$f(x)=a*cos(x)$

this is because the cosine function is maximum at $x= 0$ and therefore, has the property that

$f(0)=a*cos(0)= a$

in other words it contains the point $(0, a)$ .

The function we are looking for contains the point $(0, 3)$ ; therefore, its amplitude must be 3, or

$f(x)=3cos(x)$

we see that this function satisfies our conditions: $f(x)$ has amplitude of 3, and it passes through the point (0, 3) because $f(0)=3$

8 0

2 years ago

Read 2 more answers

A contractor has at most $42 to spend on nails for a project. Finishing nails cost $0.45 per pound and common nails cost $0.60 p

mojhsa [17]

Question:

A contractor has at most $42 to spend on nails for a project. Finishing nails cost $0.45 per pound and common nails cost $0.60 per pound. He would like to purchase at least 30 pounds of nails total. Write a system of linear inequalities

Answer:

The system of linear inequalities are:

$x + y\geq 30\\\\0.45x+0.60y\leq 42$

Solution:

Let "x" be the pounds of finishing nails

Let "y" be the pounds of common nails

Given that,

He would like to purchase at least 30 pounds of nails total.

"at least" means that he can purchase 30 pounds or more than 30 pounds also

So, we have to use "greater than or equal to" symbol

$x + y\geq 30$

From given,

Cost of 1 pound of finishing nail = $ 0.45

Cost of 1 pound of common nail = $ 0.60

A contractor has at most $42 to spend on nails for a project

"at most" means he can spend 42 or less than 42

So we have to use " less than or equal to" symbol

Thus we frame a inequality as:

$x \times 0.45 + y \times 0.60\leq 42\\\\0.45x + 0.60y\leq 42$

Thus the system of inequalities are:

$x + y\geq 30\\\\0.45x+0.60y\leq 42$

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2 years ago