Answer:
x = -5 y = -3
Step-by-step explanation:
-3x + 2y = 9
multiply the 2nd equation by 3 to set it up for elimination
3(x - 3y)= 3(4)
3x-9y = 12
so now combine both to add
-3x + 2y = 9
3x - 9y = 12
Adding both gives you
-7y = 21
divide both by -7 and you get
y = -3
and you substitute y back into equation to get x
x - 3 (-3) = 4 gives you
x + 9 = 4
x = 4 - 9
x = -5
Answer:
7:42
Step-by-step explanation:
Answer:
Nobody likes a short, one-word-answer. Let’s make sure other people understand everything.
Step-by-step explanation:
By lisa Simpson
The answers are: 4.5 g and 56.25 g respectively.
Since the first type of measurement in this question is weight or mass, I'll suppose that the percentage concentration is % mass/mass. For that type of concentration measurement, just multiply the percentage by the total mass to get the mass of the wanted material.
So 150 g * 3% = 150 g * 0.03 = 4.5g
For the 8% solution with the same amount of dry substance, use the ratio of percentages, multiplied by the mass of the first solution to get the wanted amount of new solution:
3/8 * 150 g = 56.35 g
