SOLUTION: let f= -3x+4 and g= -x^2+4x+1 find the following: g(-2) f(4)-g(4) These two problems are giving me a headache. Please show me step by step how to solve so I can see what I'

Algebra ->  Functions -> SOLUTION: let f= -3x+4 and g= -x^2+4x+1 find the following: g(-2) f(4)-g(4) These two problems are giving me a headache. Please show me step by step how to solve so I can see what I'      Log On


   

Question 122742: let f= -3x+4 and g= -x^2+4x+1 find the following:
g(-2)
f(4)-g(4)
These two problems are giving me a headache. Please show me step by step how to solve so I can see what I'm doing wrong. Thank you in advance for your help
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
Let +f=+-3x%2B4 and g=+-x%5E2%2B4x%2B1
find the following:
g%28-2%29+
f%284%29-g%284%29
to find g%28-2%29+, plug in x=-2 intog=+-x%5E2%2B4x%2B1
g%28-2%29=+-%28-2%29%5E2+%2B+4%28-2%29+%2B+1
g%28-2%29+=+-+4+%96+8+%2B+1
g%28-2%29+=+-12+%2B+1
g%28-2%29+=+-11
Now find f%284%29 and g%284%29
+f%284%29+=+-3%284%29%2B+4
+f%284%29+=+-12+%2B+4
+f%284%29+=+-8+

g%284%29=+-%284%29%5E2+%2B+4%284%29+%2B+1
g%284%29+=+-+16+%2B+16+%2B+1
g%284%29+=+1


Then you have:
f%284%29-g%284%29+=+-8+-+1
f%284%29-g%284%29+=+-9