Answer:
x = 2.25 y = 0.75
Step-by-step explanation:
2x = 9.5- 5
2x = 4.5
x = 4.5 ÷ 2
x = 2.25
know we now what is x so in the second one we evaluate x
3(2.25) + 5y = 10.5
6.75 + 5y = 10.5
5y = 10.5- 6.75
5y = 3.75
y = 3.75 ÷ 5
y = 0.75
that's it !
if you want to check your answer you can evaluate x and y so it will be like
2×2.25 + 5
= 4.5 + 5 = 9.5
and
3× 2.25 +5×0.75
= 6.75 + 3.75 = 10.5
X = amount of the 18% solution
y = amount of the 40% solution
we know the 18% solution has only 18% of alcohol, the rest is maybe water or something, now, how many liters is 18%? well, 18% of anything is just (18/100) * anything, so, 18% of x is just (18/100) *x or 0.18x, and that's how many liters are there.
likewise, how many liters are there in the 40% solution? well, (40/100) * y, or 0.4y, that many.
we know the mixture has to yield 10 liters at 20% alcohol, how many liters of only alcohol is that? well, (20/100) * 10, or 2 liters.


how much of the 40% solution? well y = 10 - x
Answer:
Step-by-step explanation:
If you are rounding to nearest tenth
2.6 1.9
Nearest hundredth
2.6 1.87
If the number to the right of the one you want to round is 5 or above, you go up a number. If it's below, you go down 1.
Hope this helps.
Answer:
-4sinθcosθ
Step-by-step explanation:
Note:
1. (a + b)^2 = a^2 + 2ab + b^2
2. (a - b)^2 = a^2 - 2ab + b^2
3. sin^2θ + cos^2θ = 1
(sinθ -cosθ)^2 - (sinθ + cosθ)^2
= sin^2θ - 2sinθcosθ + cos^2θ - (sin^2θ + 2sinθcosθ + cos^2θ)
= sin^2θ + cos^2θ - 2sinθcosθ - (sin^2θ + cos^2θ + 2sinθcosθ)
= 1 - 2sinθcosθ - (1 + 2sinθcosθ)
= 1- 2sinθcosθ -1 - 2sinθcosθ
= - 2sinθcosθ - 2sinθcosθ
= -4sinθcosθ
Answer:
hi
Step-by-step explanation: