Question

Evaluate zx-xy-7 use x=-3, y=8, and z=-9*​

Answer 1

44

Explanation:

Evaluate z x - x y - 7 where x = -3, y = 8 and z = -9:

z x - x y - 7 = -9 (-3) - -3×8 - 7

Hint: | Multiply -9 and -3 together.

-9 (-3) = 27:

27 - -3×8 - 7

Hint: | Multiply -1 and -3 together.

-(-3) = 3:

27 + 3×8 - 7

Hint: | Multiply 3 and 8 together.

3×8 = 24:

27 + 24 - 7

Hint: | Evaluate 27 + 24 using long addition.

| 1 |

| 2 | 7

+ | 2 | 4

| 5 | 1:

51 - 7

Hint: | Subtract 7 from 51.

| 4 | 11

| 5 | 1

- | | 7

| 4 | 4:

Answer: 44

Answer 2

44

Explanation:

1. substitute variables with their constants

(-9)(-3) - (-3)(8) - 7

2. multiply all like terms

(27) - (-24) - 7

3. Combine all like terms

27 + 24 - 7

51 - 7

= 44