Evaluate the expressions:
1. -8x when x=6
2. 3xsquared-5x when x=-2
3. -4((the absolute value sign) y-12 (the absolute value sign))when y=5
You can do these. Just substitute the indicated number value or y in the equation and do the computation.
For example, in #3, if y = 5, y-12 is -7 and the absolute value of that is +7. Multiply that by 4 for the answer.
Now you try the others. Show your work if you need further help.
How are these:
1. -48
2. 22
3. -28
all correct.
whoa.i dunno
To evaluate each expression, we substitute the given value for the variable and perform the necessary calculations.
1. -8x when x = 6:
Substitute x = 6 into the expression:
-8(6)
Multiply:
-48
Therefore, the value of -8x when x = 6 is -48.
2. 3x^2 - 5x when x = -2:
Substitute x = -2 into the expression:
3(-2)^2 - 5(-2)
Simplify inside the parentheses first:
3(4) + 10
Multiply:
12 + 10
Add:
22
Therefore, the value of 3x^2 - 5x when x = -2 is 22.
3. -4|y - 12| when y = 5:
Substitute y = 5 into the expression:
-4|5 - 12|
Simplify inside the absolute value:
-4|-7|
The absolute value of -7 is 7 since it represents the distance from -7 to 0 on the number line.
Substitute this absolute value back into the expression:
-4(7)
Multiply:
-28
Therefore, the value of -4|y - 12| when y = 5 is -28.