I need help solving this problem
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Answer:
[tex](x,f(x)) = (-1,8)[/tex] -- Another point
[tex]a = 8[/tex]
Step-by-step explanation:
Given
[tex]f(x) = a|x|[/tex]
[tex](x,f(x)) = (1,8)[/tex]
Solving (a): Another point
Substitute 1 for x and 8 for f(x) in [tex]f(x) = a|x|[/tex]
[tex]8 = a|1|[/tex]
Remove absolute bracket
[tex]8 = a*1[/tex]
[tex]8 = a[/tex]
[tex]a = 8[/tex]
Substitute 8 for a in [tex]f(x) = a|x|[/tex]
[tex]f(x) = 8|x|[/tex]
Let x = -1
[tex]f(x) = 8|-1|[/tex]
Remove absolute bracket
[tex]f(x) = 8*1[/tex]
[tex]f(x) = 8[/tex]
So, another point is:
[tex](x,f(x)) = (-1,8)[/tex]
Solving (b): The value of a
This has been solved in (a) above
[tex]a = 8[/tex]