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#1 2009-06-07 22:08:31
- Dharshi
- Member
- Registered: 2006-10-31
- Posts: 56
Maths
If f (g(x)) =6,where f(x) =2x+3 and g(x) = 3x-4, thenx, to the nearest tenths is equal to______
the answer given is 1.5
Can anyone help me with this?
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#2 2009-06-07 22:16:09
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Maths
I get a different answer.
Replacing the functions in the equation with their definitions:
f(3x-4) = 6
2(3x-4) +3 = 6
6x-5 = 6
x = 11/6 ≈ 1.8
Alternatively, you could solve 2(g(x))+3 = 6 for g(x), then use that in g(x) = 3x-4 to get x.
Either way, 1.8 is the answer.
Why did the vector cross the road?
It wanted to be normal.
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