Answer:
3x^2 -2x + 1 =3(x^2-2/3x+1/3)=3(x-1/3)^2+2/9*3= 3(x-1/3)^2+2/3
(x-1/3)^2 is greater or equal to zero
3(x-1/3)^2 is greater or equal to zero
and 2/3 is greater than zero
So there sum is greater than zero
Proved
Step-by-step explanation:
3x^2 -2x + 1 =3(x^2-2/3x+1/3)
Consider x^2-2/3x+1/3
Remember that (a-b)^2 =a^2-2ab+b^2
x^2=a^2
a=x
-2/3x= -2*x*b
b=1/3
S0 (x-1/3)^2= x^2-2/3x+1/9
x^2-2/3x+1/3= x^2-2/3x+1/9+1/3-1/9= (x-1/3)^2+2/9
3x^2 -2x + 1 =3(x^2-2/3x+1/3)=3(x-1/3)^2+2/9*3= 3(x-1/3)^2+2/3
(x-1/3)^2 is greater or equal to zero
3(x-1/3)^2 is greater or equal to zero
and 2/3 is greater than zero
So there sum is greater than zero
Proved

now, notice, we use the decimal format for the percent, namely 17% is 17/100 or 0.17 and so on
so.... we know, whatever "x" and "y" is, they must add up to 100 grams
thus x + y = 100
and whatever the concentrated amount is, it must add up to 17 grams for the composition
thus 0.1x + 0.2y = 17

solve for "x", to see how much is needed of the 10% alloy
what about "y"? well, y = 100 - x
Answer:
4
Step-by-step explanation:
2/5*3000 = 1200 seniors
then
3000 - 1200 = 1800 students not seniors
therefore
4/5* 1200 = 960 do not like rock climbing
and
9/10** 1800 = 1620 also do not like it:
"how many students are in favor of this idea?"
subtract the "don't likes" from 3000
3000 - (960+1620) = 420 like rock climbing:
3x-x+2=4
Answer:
anwer is 4 i m not sure
of i m right plz give me the brainliest