Respuesta :

Answer:

x = 7.9

Step-by-step explanation:

-2.3x + 4.2x = 15.01

combine like terms

1.9x = 15.01

divide both sides by 1.9

x = 7.9

-2.3x + 4.2x = 15.01         original equation

1.9x = 15.01                    combine like terms

1.9x/1.9 = 15.01/1.9        divide both sides by 1.9 to get x alone

x = 7.9                           simplify

CHECK YOUR WORK:

plug in the solution to x into the original equation like so:

-2.3(7.9) + 4.2(7.9) = 15.01        original equation w/ substitute for x

-18.17 + 33.18 = 15.01                simplify multiplication

15.01 = 15.01                             simplify addition

When you get an answer like this, you know that the solution to x that you found is correct.