Find the mistake in the following set of steps in a student’s attempt to solve 5xx+2≥xx+25, for xx. What is the correct solution set?
5x+2≥x+2/5
5(x+2/5)≥x+2/5 (factoring out 5 on the left side)
5≥1 (dividing by (x+2/5))
So, the solution set is the set of all real numbers.

At the left side of the inequality we have a factor ( x + 2/5 ) and you can divide, but to keep the inequality you have to do the same at the right hand side of the inequality and x+ 2/5 are two terms. You can pass x + 2/5 to the right shanging their sign as follow

5*(x+2/5) -x -2/5 ≥ 0 ⇒ 5x + 2 - x -2/5 ≥ 0

4x + 2 + 2/5 ≥0 ⇒ 4x + 12/5 ≥ 0 ⇒ ( 20x + 12)/5 ≥ 0

20x + 12 ≥0 ⇒20x ≥-12 x ≥ - (12/20) or x ≥ -3/5

Find the mistake in the following set of steps in a student’s attempt to solve 5xx+2≥xx+25, for xx. What is the correct solution set? 5x+2≥x+2/5 5(x+2/5)≥x+2/5 (factoring out 5 on the left side) 5≥1 (dividing by (x+2/5)) So, the solution set is the set of all real numbers.

Respuesta :

Otras preguntas

Find the mistake in the following set of steps in a student’s attempt to solve 5xx+2≥xx+25, for xx. What is the correct solution set?
5x+2≥x+2/5
5(x+2/5)≥x+2/5 (factoring out 5 on the left side)
5≥1 (dividing by (x+2/5))
So, the solution set is the set of all real numbers.