Question

Solve the following expression for x: 81=3(x+y)^3

x = 243 - y

x = 27 - y

x = 3 - y

x = 9 - y

Answer 1

@Michele_Laino

Answer 2

@Miracrown

Answer 3

Ill try to help you but I'm not gonna put a answer if i think I'm wrong

Answer 4

\(81=3(x+y)^3\)

Divide both sides by 3.
What do you get?

Answer 5

27

Answer 6

what three am i taking away on the side though the exponent or the first 3

Answer 7

@mathstudent55

Answer 8

@Michele_Laino

Answer 9

hint:
we can write this:
\[\Large {\left( {x + y} \right)^3} = \frac{{81}}{3} = 27\]

Answer 10

ok then how do i get rid of the exponent

Answer 11

you have to take the third rooth of both sides

Answer 12

so how would i do that?

Answer 13

how do you takw the 3 root of both sides

Answer 14

Correct.

\(27=(x+y)^3\)

Now we notice that \(27 = 3^3\), so we write:

\(3^3 = (x + y)^3\)

If the third power of 3 equals the third power of x + y, then 3 must equal x + y.
You can also take the cubic root of both sides.

\(3 = x + y\)

There is only one step left.
Subtract y from both sides.

Answer 15

so would it be 3-y=x @Michele_Laino
or 9-y= x

Answer 16

it is the first one, namely
x+y=3

Answer 17

ok

Answer 18

The following equation is used to determine the kinetic energy of an object: E=1/2mv^2. Solve for m:

Answer 19

@Michele_Laino

Answer 20

would it be 2E/ v^2

Answer 21

@mathstudent55

Answer 22

correct!

Answer 23

Thank you

Answer 24

Write an expression for the following description: 23 less than the product of x and 6.
6x-23 is that right

Answer 25

@Michele_Laino

Answer 26

yes!