Answer:
2
Step-by-step explanation:
let 'x' = number
x³ - x² = 2x
x³- x² - 2x = 0
x(x² - x - 2) = 0
x(x - 2)(x + 1) = 0
x = -1, 0, 2
the only positive solution is the number 2
Answer:
Wyzant
ALGEBRA WORD PROBLEM
Dorian S. asked • 06/28/17
THREE LINEAR EQUATIONS WITH THREE VARIABLES
A chemist has three different acid solutions. The first acid solution contains 15% acid, the second contains 25%,
and the third contains 70%. He wants to use all three solutions to obtain a mixture of 40 liters containing 45%
acid, using 2 times as much of the 70% solution as the 25% solution. How many liters of each solution should be used?
How to set up as three linear equations to find the answer?
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Arthur D. answered • 06/28/17
TUTOR 4.9 (67)
Forty Year Educator: Classroom, Summer School, Substitute, Tutor
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set up 2 equations
the first equation...
15%*x+25%*y+70%*2y=45%*40
0.15x+0.25y+1.4y=0.45*40
0.15x+1.65y=18
multiply all terms by 100
15x+165y=1800
divide all terms by 15
x+11y=120
the second equation...
x+y+2y=40
x+3y=40
x=40-3y
substitute into the first equation x+11y=120
40-3y+11y=120
40+8y=120
8y=120-40
8y=80
y=80/8
y=10 liters
x+3*10=40
x+30=40
x=40-30
x=10 liters
10 liters of 15%, 10 liters of 25%, and 20 liters of 70%
check:
10*15%=1.5
10*25%=2.5
20*70%=14
1.5+2.5+14=18
18/40=9/20=45/100=45%
45%*40=18
hope it helps
please mark brainliest
Direct variation is y=kx, inverse variation is y=k/x....
-5y=-2x divide both sides by -5
y=2.5x
So this is a direct variation with a constant of 2.5
Answer:
B
Step-by-step explanation:
[z^4/6²]^-3 = z^-12/6^-6 = 6^6/z^12
Less than means subtract. So, 0.02 less than 1.423 is 1.423 - 0.02 which equals >>> 1.403
