## Nullify 3 years ago Evaluate the following expression using the values given. Find 4x - y - 2z if x = -2, y = 3, and z = -2

1. dgo

what are you having trouble with?

2. dgo

you substitute the values given for the appropriate variable then follow PEMDAS

3. Nullify

Substitute what values?

4. dgo

x = -2, y = 3, and z = -2

5. dgo

the numbers are values

6. Nullify

Ohh okay 1 sec

7. Nullify

is it 9?

8. dgo

no, first just sub the values and rewrite the full expression with the x y z

9. dgo

i mean without the x y z

10. dgo

you can rewrite it here

11. dgo

do u understand what im asking?

12. Nullify

4(-2) - 3 - 2(-2)

13. dgo

exactly! now do you know how to solve that?

14. Nullify

I do the ones in parentheses first right?

15. dgo

well parentheses come first, but here what is inside the parentheses is just a number, there nothing to do in there. so you actually do multiplication first. 4(-2) is just another way, a more clear way, of saying 4 * -2

16. Nullify

I did that and I got 8 - 3 - -4

17. dgo

4 * -2 actually equals -8

18. Nullify

Ohhhhh whoops

19. dgo

whenever you multiply a negative and a positive the answer is always negative

20. Nullify

Oh so it';s -7?

21. dgo

boom! nice job

22. Nullify

Haha, thanks!

23. dgo

:) good luck