Let
x = number of liters of the 40% salt solution
y = number of liters of the 20% salt solution
The two amounts (x and y) must combine to 1500 liters, so
x+y = 1500
we can solve for y to get
y = 1500-x
after subtracting x from both sides
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If we have x liters of the 40% salt solution (composed of pure salt plus other stuff) then we have exactly 0.40*x liters of pure salt. Simply multiply the decimal form of the percentage with the amount of solution.
Similarly, if we have y liters of the 20% solution, then we have 0.20*y liters of pure salt
Combined, we have 0.40*x + 0.20*y liters of pure salt all together.
We want 1500 liters of a 28% solution, so we want 1500*0.28 = 420 liters of pure salt
Equate the two expressions (0.40*x + 0.20*y and 420) to get
0.40*x + 0.20*y = 420
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We have the equation 0.40*x + 0.20*y = 420 and we also know that y = 1500-x
Let's use the substitution property now
0.40*x + 0.20*y = 420
0.40*x + 0.20*( y ) = 420
0.40*x + 0.20*( 1500 - x ) = 420 ... note how y is replaced with 1500-x
Now we can solve for x
0.40*x + 0.20*( 1500 - x ) = 420
0.40*x + 0.20*(1500) + 0.20*(-x) = 420
0.40*x + 300 - 0.20x = 420
0.40*x - 0.20x + 300 = 420
0.20x + 300 = 420
0.20x + 300 - 300 = 420 - 300
0.20x = 120
0.20x/0.20 = 120/0.20
x = 600
Now that we know x, use this to find y
y = 1500-x
y = 1500-600 ... plug in x = 600 (ie replace x with 600)
y = 900
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Answers:
We need 600 liters of the 40% solution
We need 900 liters of the 20% solution
<span>The correct answer is 2x</span>²<span>-16x+30.
Explanation<span>:
(p*q)(x) is a composition of the two functions p(x) and q(x); it is the same as p(q(x)). We replace every x in p(x) with our value of q(x), x-3:
instead of 2x</span></span>²<span><span>, we have 2(x-3)</span></span>²<span><span>, and instead of -4x, we have -4(x-3).
This gives us 2(x-3)</span></span>²<span><span>-4(x-3). This is the same as 2(x-3)(x-3)-4(x-3).
Multiplying, we have
2(x*x-3*x-3*x-3(-3))-(4*x-4*3)
=2(x</span></span>²<span><span>-3x-3x+9)-(4x-12)
=2(x</span></span>²<span><span>-6x+9)-4x+12.
Using the distributive property gives us
2*x</span></span>²<span><span>-2*6x+2*9-4x+12
=2x</span></span>²<span><span>-12x+19-4x+12.
Combine like terms, and we have 2x</span></span>²<span><span>-16x+30.</span></span>
Plane R and plane P intersect at AB.
Planes are when 3 points that are not on the same line can be used to describe a plane. Plane P is horizontal and Plane R is vertical and these 2 planes intersect at line AB. Intersecting is where these 2 planes meet, therefore line AB is common to both planes.
A possible solution to the inequality is 2 hotdogs and 8 tacos.
Let x represents the number of hotdogs purchased and y represents the number of tacos purchased.
Gabriella has $30 to spend and must buy a minimum of 9 hotdogs and tacos altogether.
Hence:
4x + 2y ≤ 30 (1)
x + y ≥ 9 (2)
Also:
x ≥ 2 (3)
A possible solution to the inequality is 2 hotdogs and 8 tacos.
Find out more on inequality at: brainly.com/question/241541
255 l ------ 340km
x l -------- 100km
100*255=340x
25500=340x
x=75 litres
