A. 11
B. 3
C. -17
D. -1
Evaluate the expression for the given value of the variable(s). -x 2 - 4x; x = -3?
2016-06-27 5:53 pm
回答 (5)
2016-06-27 6:03 pm
When x = -3 :
The expression -x² - 4x
= -(-3)² - 4(-3)
= -9 + 12
= 3
The answer is : B. 3
The expression -x² - 4x
= -(-3)² - 4(-3)
= -9 + 12
= 3
The answer is : B. 3
2016-06-27 6:01 pm
Well,
f(x) = -x^2 - 4X
therefore
f(-3) = - (-3)^2 - 4*(-3)
= -9 + 12
= 3
B. 3 <--- answer
hope it' ll help !!
f(x) = -x^2 - 4X
therefore
f(-3) = - (-3)^2 - 4*(-3)
= -9 + 12
= 3
B. 3 <--- answer
hope it' ll help !!
2016-06-27 6:56 pm
plug -3 in for x
-(-3)^2-4(-3) = -9 + 12 = 3
-(-3)^2-4(-3) = -9 + 12 = 3
2016-06-27 6:38 pm
B. 3
−x²−4x
= −(−3)²−4(−3)
= −9+12
= 3
2016-06-27 6:00 pm
So x2 being a separate variable, yes? Just use 'y' or some other letter next time.
General form:
-x2 - 4x; x2 is y
-y - 4x; x = -3
-y - 4(-3)
-y + 12
A.
-(11) + 12 = 1
B.
-(3) + 12 = __
You can take it from here. As long as I read x2 correctly, this should go smoothly unless you have any questions.
EDIT:
Ah, you meant x². I should've realized that. You can also write it as x^2 if you don't know how to type ²
General form:
-x2 - 4x; x2 is y
-y - 4x; x = -3
-y - 4(-3)
-y + 12
A.
-(11) + 12 = 1
B.
-(3) + 12 = __
You can take it from here. As long as I read x2 correctly, this should go smoothly unless you have any questions.
EDIT:
Ah, you meant x². I should've realized that. You can also write it as x^2 if you don't know how to type ²
收錄日期: 2021-04-18 15:17:18
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