Question

3x minus one over five times the quantity 10x plus 5 equals 6 Step 1: 3x – 2x – 1 = 6 Step 2: x – 1 = 6 Step 3: x – 1 – 1 = 6 – 1 Step 4: x = 5 In which step was the error made and why?

Answer 1

The first step, I think, because I think that they made a mistake setting up the equation. I believe that the equation should be 3x-1/5(10x+5)=6.

Answer 2

The error was made in third step, because in this step 1 is subtracted instead of adding.

Explanation:

Given equation,

3x minus one over five times the quantity 10x plus 5 equals 6

`3x-(1)/(5)(10x+5)=6`

Step 1 : Apply distributive property on the left side,

`3x-2x-1=6`

Step 2 : By subtraction property on the left side,

`x-1=6`

Step 3 : Adding 1 on the both sides ( for isolating x on left side )

`x-1+1=6+1`

Step 4 : Combine the like terms,

`x=7`

Hence, by the above explanation it is clear that there was an error in third step,

Reason : 1 is subtracted instead of adding.