Let's write 2 equations from the two statements given.
<em>Sarah spent 10 dollars on both oranges and apples</em>
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Let the price of oranges be "x" and price of apples be "y", thus we can write:

Oranges cost 3 less than apples, thus we can say:

We can substitute this into the first equation and solve for y:

Thus, let's solve for x now,

We want the price of oranges (x), thus,
<em>Price of Oranges = $3.50</em>
(-5/3)•(-6/1)=(30/3)
(30/3) simplified is (10/1)
Let us convert the percentages to decimal format first.. so 5% is just 5/100 or 0.05 and 15% is just 15/100 or 0.15
so hmmm, so, let's say it needs "x" amount and "y" amount of each respectively, so, whatever "x" and "y" are, they must add up to 100, and whatever their concentration is, must add up to what the mixture yields
thus

solve for "x"
what's "y"? well, y = 100 - x
The discriminant is

which is 0.
Since the discriminant is 0, there is only one real solution.
Answer:
w = 4
Step-by-step explanation:
you would do this by re-arranging the equation
6 = 5w-10-w (move w to the other side)
6 = 4w-10 (because 5w-w = 4w)
6+10=4w (move 10 to the other side)
16 = 4w (add 6 and 10)
4 = w (divide both sides by 4)