Question

How do you solve `3( 5x - 4) = 8x - 4`?

Answer 1

PESADM Multiply across the parenthesis Combine like terms by adding and subtracting and then solve for x by dividing.

Explanation:

PEMDAS is the correct order of operations working forward.
PESADM is the reverse order of operations when trying to find something unknown ( or lost). (Think if you lose something in PE class you are a SAD M(an)

So in solving this problem first use the distributive property to remove the Parenthesis `3 xx ( 5x - 4 )` this gives

`3 xx 5x - 3 xx 4` This gives

15x - 12 Putting this into the original equations gives.

15x -12 = 8x -4 Now combine like terms by adding and subtracting

Subtract 8 x from both sides

15x - 8x -12 = 8x - 8x -4 Gives

7x - 12 = -4

Next add 12 to both sides

7x - 12 + 12 = -4 + 12 Gives

7x = + 8

Now divide both sides by 7

`( 7x)/7 = 8/7` Gives

x = `8/7`

Remember in solving an equation use PEMDAS backwards.
PESAD M

Answer 2

`x=8/7`

Explanation:

The first step is to distribute the bracket.

`15x-12=8x-4`

Now collect x terms on the left side of the equation and numeric values on the right.

subtract 8x from both sides of the equation.

`15x-8x-12=cancel(8x)cancel(-8x)-4`

`rArr7x-12=-4`

add 12 to both sides.

`7xcancel(-12)cancel(+12)=-4+12`

`rArr7x=8`

To solve for x , divide both sides by 7.

`(cancel(7) x)/cancel(7)=8/7`

`rArrx=8/7" is the solution"`