What is 643.072 rounded to the nearest tenth thank you for helping

Find the product of all real values of r for which 1/2x=r-x/7

Dahasolnce [82]

Answer:

$r = \±\sqrt{14$

$Product = -14$

Step-by-step explanation:

Given

$\frac{1}{2x} = \frac{r - x}{7}$

Required

Find all product of real values that satisfy the equation

$\frac{1}{2x} = \frac{r - x}{7}$

Cross multiply:

$2x(r - x) = 7 * 1$

$2xr - 2x^2 = 7$

Subtract 7 from both sides

$2xr - 2x^2 -7= 7 -7$

$2xr - 2x^2 -7= 0$

Reorder

$- 2x^2+ 2xr -7= 0$

Multiply through by -1

$2x^2 - 2xr +7= 0$

The above represents a quadratic equation and as such could take either of the following conditions.

(1) No real roots:

This possibility does not apply in this case as such, would not be considered.

(2) One real root

This is true if

$b^2 - 4ac = 0$

For a quadratic equation

$ax^2 + bx + c = 0$

By comparison with $2x^2 - 2xr +7= 0$

$a = 2$

$b = -2r$

$c =7$

Substitute these values in $b^2 - 4ac = 0$

$(-2r)^2 - 4 * 2 * 7 = 0$

$4r^2 - 56 = 0$

Add 56 to both sides

$4r^2 - 56 + 56= 0 + 56$

$4r^2 = 56$

Divide through by 4

$r^2 = 14$

Take square roots

$\sqrt{r^2} = \±\sqrt{14$

$r = \±\sqrt{14$

Hence, the possible values of r are:

$\sqrt{14$ or $-\sqrt{14$

and the product is:

$Product = \sqrt{14} * -\sqrt{14}$

$Product = -14$

8 0

3 years ago

Graph each exponential function <br> Y=4x

jeka94

<span>ahh okay i was going to say...thats a straight line haha....okay well lets see....what is 4^0? 1 right? what is 4^1? 4 ...4^2? 16 ...4^3? 64....make a graph with those points</span>

5 0

3 years ago

A company charges $7 for a T-shirt and ships any order for $22. A school principal ordered a number of T-shirts for the school s

Harlamova29_29 [7]

Answer: The awnser would be D

5 0

3 years ago

Write the congruency statement for the triangles. _______In triangles MNO and JKL, there are two congruent sides and included an

mafiozo [28]

Answer:

ΔJKL ≅ ΔMNO by SAS

Step-by-step explanation:

The question is incomplete, the question is as following:

ΔMNO is shown.

Which Δ below can be shown to be congruent to ΔMNO with only the given information?

Name the postulate that justifies your answer (SAS, AAS, HL, ASA or SSS).

Write the congruency statement for the triangles.

And see the attached figure which represent ΔMNO

==========================================================

Check the given options to see which triangle from the option will be congruent to ΔMNO

1. In triangles MNO and ABC, there are two congruent sides and non-included angle - which mean (angle - side - side)

The (angle - side - side) Postulate does not exist because an angle and two sides does not guarantee that two triangles are congruent.

2. In triangles MNO and DEF, there are two congruent sides - there is not enough information

3. In triangles MNO and GHI, there are three congruent angles - which mean AAA (angle - angle - angle)

The AAA Postulate does not exist because an angle and two sides does not guarantee that two triangles are congruent. This postulate is used to prove the similarity between the triangles.

4. In triangles MNO and JKL, there are two congruent sides and included angle - SAS (side - angle - side)

MN ≅ JK , MO ≅ JL , ∠M ≅ ∠J

5 0

3 years ago

Find the slope of the line that passes through the two points. (-3, -4), (6, 8)

sveticcg [70]

Answer:

Step-by-step explanation:

let (x1 , y1) = ( - 3, - 4) and (x2 , y2) = ( 6 , 8)

Slope (m)

= y2 - y1 / x2 - x1

= 8 + 4 / 6 + 3

= 12 / 9

= 4/3

7 0

3 years ago