so hmm notice, we use the decimal format for the percent, namely 15% is just 15/100 and 5% is just 5/100 and so on
whatever the amounts of "x" and "y" are, they must add up to 100 grams
thus x + y = 100
and whatever the concentrated amounts are, they'll add up to (100)(0.15)
thus
solve for "x", to see how much 5% alloy will be needed
what about "y"? well y = 100 -x
Answer:
x=6
Step-by-step explanation:
5x-10=2x+8
subtract 2x on both sides
3x-10=8
add 10 on both sides
3x=18
x=6
I think the answer its 42.91
Ok let’s solve it
5(x-2)^2-20=0
first let’s foil (x-2)
5(x^2-4x+4) -20=0
now distribute the 5
5x^2 -20x +20 -20 = 0
combine like terms
5x^2-20x=0
take the gcf
5x(x-4)=0
x=0, 4
solutions are (4,0) and (2, -20) because the original vertex form a(x-h)^2+k
