Respuesta :

kingelaina

Answer:

Adding and subtracting :D

Step-by-step explanation:

okay so after plugging in your x you should have an equation that looks like this:

5+15-4.2

because (x=5)+(3*5)- 4.2

so then you start adding and subtracting:

(5+15)-4.2

20-4.2

15.8

Hope this helps :D

texaschic101

Answer:

Step-by-step explanation:

x + 3x - 4.2....when x = 5

so we sub

5 + 3(5) - 4.2

I would then multiply the 3 and the 5

5 + 15 - 4.2

then I would add

20 - 4.2

then subtract

15.8