Let f(x)=7x2−4x+8 and g(x)=−6+4x−7x2.

What is f(x)+g(x) ?

Question

Let f(x)=7x2−4x+8 and g(x)=−6+4x−7x2.

What is f(x)+g(x) ?

misty1212 · Answer

HI!!

misty1212 · Answer

put a plus sign between them, then combine like terms

anonymous · Answer

Hi hah. SOrry, I'm not well in math...

misty1212 · Answer

$$7x^2-4x+8-6+4x-7x^2$$

misty1212 · Answer

then $7x^2-7x^2=0$ right?

anonymous · Answer

ooh.. i see now the your left with those to work with right?

misty1212 · Answer

yes

misty1212 · Answer

all the terms with $x$'s in them go bye bye (add up to zero) and you are only left with $8-6$ which you can compute even if you are not well in math

anonymous · Answer

so. they are asking for one number??

misty1212 · Answer

it turns out in this case you do only get one number for $f(x)+g(x)$

anonymous · Answer

... i'm lost now.. so ... ughhh!

misty1212 · Answer

lol what is $8-6$?

anonymous · Answer

2

misty1212 · Answer

$$7x^2-4x+8-6+4x-7x^2$$
$$7x^2-7x^2-4x+4x+8-6$$
$$\overbrace{7x^2-7x^2}^{\text{adds to zero}}\overbrace{-4x+4x}^{\text{adds to zero}}\overbrace{+8-6}^{\text{adds to 2}}$$

misty1212 · Answer

so 2 is the final answer

anonymous · Answer

so i just put 2? nothing else?

misty1212 · Answer

yes because in this case the other two terms add up to zero 
that only leaves the 2

misty1212 · Answer

it is not usually like that, just happens to be here

anonymous · Answer

thank you. >.<

misty1212 · Answer

$$\color\magenta\heartsuit$$