A. -8
B. -1
C. -16
D. -12
MATH HELP PLEASE?!!? The function f(x) varies directly with x and f(x)=32 when x=-8 What is f(x) when x=4?
2016-02-22 5:59 pm
回答 (2)
2016-02-22 6:03 pm
f(x) ∝ x
Then f(x) = kx
where k is a non-zero constant.
When x = -8, f(x) = 32 :
32 = k(-8)
k = -4
Then, f(x) = -4x
When x = 4 :
f(x) = -4(4)
f(x) = -16
...... The answer is : C. -16
Then f(x) = kx
where k is a non-zero constant.
When x = -8, f(x) = 32 :
32 = k(-8)
k = -4
Then, f(x) = -4x
When x = 4 :
f(x) = -4(4)
f(x) = -16
...... The answer is : C. -16
2016-02-22 6:48 pm
y = k x
32 = - 8 k
k = - 4
f (x) = - 4 x
f (4) = - 16________Option C
32 = - 8 k
k = - 4
f (x) = - 4 x
f (4) = - 16________Option C
收錄日期: 2021-04-18 14:28:55
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