Question

5x-4(x-4)-9 при х=-3

Answer 1

5х-4(х-4)-9=5х-4х+16-9=х+7;  (сначала выражение надо упростить);

при х=-3

х+7=-3+7=7-3=4 - это ответ.

Answer 2

To evaluate the expression 5x - 4(x - 4) - 9 when x = -3, follow these steps:

1. Replace every occurrence of "x" with "-3" in the expression.
2. Perform the operations in the parentheses first.
3. Continue by evaluating the rest of the expression.

Let's go step by step:

1. Replace "x" with "-3": 5(-3) - 4(-3 - 4) - 9

2. Simplify the operations in the parentheses: 5(-3) - 4(-7) - 9

3. Perform the remaining operations: -15 + 28 - 9

4. Finally, add and subtract to get the result: -15 + 28 = 13 13 - 9 = 4

So, when x = -3, the expression evaluates to 4.