Let y = 3^x , then 9^x = (3^2)^x = (3^x)^2 = y^2, so we can write the equation as
y^2 - 10y + 9 = 0
(y - 9)(y - 1) = 0
giving y = 9 or y = 1
Therefore 3^x = 9 giving x = 2
and 3^x = 1 giving x = 0
so the solution set is {0, 2}
Note - I have assumed that the 'x' after the 10 means 'multiply'. Is that correct?
Answer:
The amount of salt required is 0.3685 grams.
Step-by-step explanation:
20.9% of 1 gram of salt is chlorine, which means the grams of chlorine in 1 gram of salt are

Now, to make 220 ppm solution, it must be that

where
is the grams of chlorine required.
We rearrange the equation and solve for 





since 1 gram of salt has 0.209 grams of chlorine, 0.07702g of chlorine corresponds to

Thus the amount of salt required is 0.3685 grams.
Answer:
False
Step-by-step explanation:
Both do not gain from the exchange. If producing 1 pumpkin is greater than 2 tomatoes, this means that Barney traded for less than he gave out in cost to produce 1 pumpkin. Barney should be demanding more tomatoes to make up the cost of producing 1 pumpkin. Fred makes a gain from the transaction. The selling price of tomatoes are less than a pumpkin. He can therefore sell 1 pumpkin to produce more than 2 tomatoes per pumpkin.
Answer:
6x-12-3x+2
Step-by-step explanation:
Answer:
$5
Step-by-step explanation:
Let the cost of one burger be $b while the cost of one small fries be s
2 burgers and 2 small fries cost $14
This means that;
2b + 2s = 14
divide both sides by 2
b + s = 7 •••••••• (i)
Three burgers and four small fries cost $23
Mathematically;
3b + 4s = 23 •••••••• (ii)
From i , we can see that s = 7- b
we can now substitute this into equation ii
3b + 4(7-b) = 23
3b + 28 -4b = 23
4b -3b = 28 -23
b = $5
one burger costs $5