All proofs start as ______.<br><br> A.) Constructions<br> B.) Conjectures<br> C.) Converses

I need help please.

Ivan

1. It is given that f(x) is 16 times the square root of x.

Putting that in mathematical terms we have,

f(x) = 16 * $\sqrt{x}$

also, y = f(x)

So, we have the function

y= 16 $\sqrt{x}$

4. We need to solve the inequality equation : 4x + 2y ≤ 6

Let us take the equation,

4x+2y ≤ 6

2y ≤ 6-4x

y ≤ $\frac{6-4x}{2}$

y ≤ 3-2x

So, any point (x,y) lies on the given inequality region, where y≤ 3-2x

5. Solving system of equations using addition method

Given:

-5x-y =38 ------> a

-6x-3y =60 -------> b

Divide the equation b by no. 3

(-6x-3y)/3 = 60/3

-2x-y = 20 -------> c

Subtracting equation c from a we have,

-5x-y - (-2x-y) = 38 - 20

-5x-y+2x+y = 18

-3x = 18

x = -6

Now, substituting the value of x in equation a, we get

-5(-6) - y =38

30-y =38

y= 30-38 = -8

y=-8

∴ x = -6 and y = -8

6. Finding composition of functions

Given : f(x) =15x + 7 ; g(x) = x² - 5x

To find : (f+g)(x)

(f+g) (x) = f(g(x))

So, replace the value of x in f(x) by g(x), where g(x)= x² - 5x

(f+g)(x) = 15(x²-5x) +7 =15x²-75x+7

∴ (f + g)(x) = 15x²-75x+7

7. System of 3 equations must be solved to find the solution

-8x-8y-5z=-6

7x-8y-9z =17

9x+2y+6z =-1

Solving by substitution method.

Isolate x from first equation :

x= (-6+8y+5z)/(-8)

Substitute this value of x in 2nd and 3rd equations.

$7 (- \frac{-6+8y+5z}{8})-8y -9z = 17$

$9(- \frac{-6+8y+5z}{8}) + 2y + 6z = -1$

Now, isolating y from the 2nd equation rewritten above, we have

y= - $\frac{107 z + 94}{120}$

Now substituting this value of y in the 3rd equation rewritten above, we have

$9(- \frac{-6+8(-\frac{107 z + 94}{120})+5z}{8}) + 2(-\frac{107 z + 94}{120}) + 6z = -1$

Isolating z from above equation, we have

z = -2

Substitute z= -2 in the equation of y, we have

y= - $\frac{107 (-2) + 94}{120}$ = 1

y = 1

Substituting the value of y and z, in the equation of x, we have

x= (-6+8(1)+5(-2))/(-8) = 1

x = 1

∴ x=1 ; y = 1 ; z = -2

8. 5x ≤ 7

Solving the above equation, we have

x ≤ 7/5

Please see attachment for the graph.

9. The given function is : g(y) = $\sqrt{y}$ -6

The domain is the set of values of y for which there can be a value of g(y).

Here g(y) can be real only if y is greater than or equal to 0.

∴ The domain of the given function is [0,∞) .

10. Given : y is a function of x.

Definition of function : A function is a relation that associates each element in the domain to one element of another set, the co-domain of the function.

∴ For each element x, in the domain, there is only one value of y in the range.

4 0

3 years ago

Find equations of the spheres with center(3, −4, 5) that touch the following planes.a. xy-plane b. yz- plane c. xz-plane

postnew [5]

Answer:

(a) (x - 3)² + (y + 4)² + (z - 5)² = 25

(b) (x - 3)² + (y + 4)² + (z - 5)² = 9

(c) (x - 3)² + (y + 4)² + (z - 5)² = 16

Step-by-step explanation:

The equation of a sphere is given by:

(x - x₀)² + (y - y₀)² + (z - z₀)² = r² ---------------(i)

Where;

(x₀, y₀, z₀) is the center of the sphere

r is the radius of the sphere

Given:

Sphere centered at (3, -4, 5)

=> (x₀, y₀, z₀) = (3, -4, 5)

(a) To get the equation of the sphere when it touches the xy-plane, we do the following:

i. Since the sphere touches the xy-plane, it means the z-component of its centre is 0.

Therefore, we have the sphere now centered at (3, -4, 0).

Using the distance formula, we can get the distance d, between the initial points (3, -4, 5) and the new points (3, -4, 0) as follows;

$d = \sqrt{(3-3)^2+ (-4 - (-4))^2 + (0-5)^2}$

$d = \sqrt{(3-3)^2+ (-4 + 4)^2 + (0-5)^2}$

$d = \sqrt{(0)^2+ (0)^2 + (-5)^2}$

$d = \sqrt{(25)}$

d = 5

This distance is the radius of the sphere at that point. i.e r = 5

Now substitute this value r = 5 into the general equation of a sphere given in equation (i) above as follows;

(x - 3)² + (y - (-4))² + (z - 5)² = 5²

(x - 3)² + (y + 4)² + (z - 5)² = 25

Therefore, the equation of the sphere when it touches the xy plane is:

(x - 3)² + (y + 4)² + (z - 5)² = 25

(b) To get the equation of the sphere when it touches the yz-plane, we do the following:

i. Since the sphere touches the yz-plane, it means the x-component of its centre is 0.

Therefore, we have the sphere now centered at (0, -4, 5).

Using the distance formula, we can get the distance d, between the initial points (3, -4, 5) and the new points (0, -4, 5) as follows;

$d = \sqrt{(0-3)^2+ (-4 - (-4))^2 + (5-5)^2}$

$d = \sqrt{(-3)^2+ (-4 + 4)^2 + (5-5)^2}$

$d = \sqrt{(-3)^2 + (0)^2+ (0)^2}$

$d = \sqrt{(9)}$

d = 3

This distance is the radius of the sphere at that point. i.e r = 3

Now substitute this value r = 3 into the general equation of a sphere given in equation (i) above as follows;

(x - 3)² + (y - (-4))² + (z - 5)² = 3²

(x - 3)² + (y + 4)² + (z - 5)² = 9

Therefore, the equation of the sphere when it touches the yz plane is:

(x - 3)² + (y + 4)² + (z - 5)² = 9

(b) To get the equation of the sphere when it touches the xz-plane, we do the following:

i. Since the sphere touches the xz-plane, it means the y-component of its centre is 0.

Therefore, we have the sphere now centered at (3, 0, 5).

Using the distance formula, we can get the distance d, between the initial points (3, -4, 5) and the new points (3, 0, 5) as follows;

$d = \sqrt{(3-3)^2+ (0 - (-4))^2 + (5-5)^2}$

$d = \sqrt{(3-3)^2+ (0+4)^2 + (5-5)^2}$

$d = \sqrt{(0)^2 + (4)^2+ (0)^2}$

$d = \sqrt{(16)}$

d = 4

This distance is the radius of the sphere at that point. i.e r = 4

Now substitute this value r = 4 into the general equation of a sphere given in equation (i) above as follows;

(x - 3)² + (y - (-4))² + (z - 5)² = 4²

(x - 3)² + (y + 4)² + (z - 5)² = 16

Therefore, the equation of the sphere when it touches the xz plane is:

(x - 3)² + (y + 4)² + (z - 5)² = 16

3 0

3 years ago

Can someone help me fast

cestrela7 [59]

Maybe try 8 penalties over 6 penalties and 16 minutes

5 0

3 years ago

I learned it before but now I forgot it. Please help!

JulijaS [17]

X should be 3,

because 8x means 8 times what number.

So 8x must be 3.

8 times 3 = 24. 24 +5 = 29.

Hope you Understand :) !

6 0

3 years ago

Read 2 more answers

Which equation can be used to solve the following word problem?

ra1l [238]

A is definitely the answer.

3 0

3 years ago

Read 2 more answers

All proofs start as ______. A.) Constructions B.) Conjectures C.) Converses