SOLUTION: This problem is giving me fits!! Please help!! Given that f(x)=x^2-13 and g(x)=18-x find (f-g)(-3)

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Question 1019690: This problem is giving me fits!! Please help!!
Given that f(x)=x^2-13 and g(x)=18-x find (f-g)(-3)
Found 2 solutions by Cromlix, MathTherapy:
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi there,
f(x) = x^2 - 13
g(x) = 18 - x
(f - g)
(x^2 - 13) - (18 - x)
Remove brackets
x^2 - 13 - 18 + x
x^2 + x - 21
(-3)
(-3)^2 + (-3) - 21
9 - 3 - 21
= -15
Hope this helps :-)

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

This problem is giving me fits!! Please help!!
Given that f(x)=x^2-13 and g(x)=18-x find (f-g)(-3)
f%28x%29+=+x%5E2+-+13		;		g(x) = 18 – x

(f- g)(- 3) means: f(- 3) – g(- 3)



f%28x%29+=+x%5E2+-+13

f%28-+3%29+=+%28-+3%29%5E2+-+13

f(- 3) = 9 – 13, or – 4



g(x) = 18 – x

g(- 3) = 18 - - 3, or 18 + 3, or 21



(f- g)(- 3) = f(- 3) – g(- 3) = - 4 – 21 = highlight_green%28-+25%29