How do you solve 2x/3+9=-72x3+9=7?

2 Answers

Use the formula PESADM
x = -24x=24

Explanation:

In solving for an unknown always work backwards.
First remove any Parenthesis and Exponents

x/3x3 is actually a parenthesis (x/3)(x3)

To remove the parenthesis multiply everything by 3. This gives

cancel3 xx 2(x/cancel3) + 3 xx 9 = 3 xx -7 The result is

2x + 27 = - 21

Now that the PE is taken care of do SA (subtraction and addition)

Subtract 27 or add - 27 to both sides This gives

2x + 27 - 27 = -21 -27" " The result is

(subtracting from a negative gives more negatives)
A negative goes down, adding another negative goes further down. So the answer is very down
Think " I fell into a burning ring of fire I went down down down and the flame went higher and it burns burns burns the ring of fire".

2x = - 48

The PE and the SA are taken care of now do the DM

Divide both sides by 2" " This gives

(2x)/2 = -48/2 " " The result is

x = -24 ( a negative divided by a positive is a negative)

PESADM Think if you find you lost your cell phone in PE you are a SAD M(am)

Oct 19, 2016

It is not clear what is intended in the first term? 2 x/3
There are two possible solutions.
x = -54 " or " x = -24

Explanation:

It is not clear what is intended in the first term? 2 x/3

Is this to be regarded as a mixed fraction, which is generally not used in algebra?

There is nothing to indicate that is is a multiplication?

One of " "2(x/3) " "2*x/3 " " 2xx x/3 would have been clearer

Let's look at both possibilities.

Option 1

Write 2 x/3 as an improper fraction, giving (6+x)/3

(6+x)/3 +9color(red)(-9) = -7color(red)(-9)" "larr add -9 to both sides

(color(blue)(3xx)(6+x))/3 = -16color(blue)(xx3)color(white)(xxxxxxxxx)larr xx 3 on both sides

6+x = -48" "larr subtract 6 from both sides

x = -48-6

x = -54

Option 2

2(x/3) +9color(red)(-9) = -7color(red)(-9)" "larr subtract 9 from each side

(color(blue)(3xx)2x)/3 = -16color(blue)(xx3)color(white)(xxxxxxxxx)larr xx 3 on both sides

2x = -48

x = -24