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3 years ago

Brine is a solution of salt and water. If a tub contains 50 gallons of a 5% solution of brine, how much water must

1 answer:

8 0

Let $w$ be the amount of water that evaporates. At the start, the solution in the tub consists of 2.5 gallons of salt (5% of 50 gallons). After $w$ gallons of water evaporates, we're left with a solution with total volume $50-w$ gallons, and 8% of this amount should be salt, or $0.08(50-w)$ gallons of salt. The amount of salt in the tank before and after evaporation remains unchanged, so

$2.5=0.08(50-w)\implies2.5=4-0.08w\implies0.08w=1.5\implies\boxed{w=18.75}$

gallons of water need to be evaporated.

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An __________ is used to indicate the repeating part of a repeating decimal.

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Line above the repeating number

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3 years ago

Please help Which of the following inequalities is graphed on the coordinate plane?

Gekata [30.6K]

Answer:

The inequality which represents the graph is y ≤ -2x + 1 ⇒ A

Step-by-step explanation:

To solve the question you must know some facts about inequalities

If the sign of inequality is ≥ or ≤, then it represents graphically by a solid line

If the sign of inequality is > or <, then it represents graphically by a dashed line

If the sign of inequality is > or ≥, then the area of the solutions should be over the line

If the sign of inequality is < or ≤, then the area of the solutions should be below the line

Let us study the graph and find the correct answer

∵ The line represented the inequality is solid

∴ The sign of inequality is ≥ or ≤

→ That means the answer is A or B

∵ The shaded area is the area of the solutions of the inequality

∵ The shaded area is below the line

∴ The sign of inequality must be ≤

→ That means the correct answer is A

∴ The inequality which represents the graph is y ≤ -2x + 1

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3 years ago

Which expressions are equivalent to Negative 2 (5 x minus three-fourths)? Check all that apply.

puteri [66]

Answer:

hope it's help you

Step-by-step explanation:

negative 10×three-halves

6 0

3 years ago

Read 2 more answers

Find the vertex of the graph of the function.

lapo4ka [179]

Answer: The correct options are (1) (5,10), (2) (3,-3), (3) x = -1, (4) $y=(x+2)^2+3$ , (5) 21s and (6) 0, -1, and 5.

Explanation:

Te standard form of the parabola is,

$f(x)=a(x-h)^2+k$ .....(1)

Where, (h,k) is the vertex of the parabola.

(1)

The given equation is,

$f(x)=(x-5)^2+10$

Comparing this equation with equation (1),we get,

$h=5$ and $k=10$

Therefore, the vertex of the graph is (5,10) and the fourth option is correct.

(2)

The given equation is,

$f(x)=3x^2-18x+24$

$f(x)=3(x^2-6x)+24$

To make perfect square add $(\frac{b}{2a})^2$ , i.e., $9$ . Since there is factor 3 outside the parentheses, so subtract three times of 9.

$f(x)=3(x^2-6x+9)+24-3\times 9$

$f(x)=3(x-3)^2-3$

Comparing this equation with equation (1),we get,

$h=3$ and $k=-3$

Therefore, the vertex of the graph is (3,-3) and the fourth option is correct.

(3)

The given equation is

$f(x)=4x^2+8x+7$

$f(x)=4(x^2+2x)+7$

To make perfect square add $(\frac{b}{2a})^2$ , i.e., $1$ . Since there is factor 4 outside the parentheses, so subtract three times of 1.

$f(x)=4(x^2+2x+1)+7-4$

$f(x)=4(x+1)^2+3$

Comparing this equation with equation (1),we get,

$h=-1$ and $k=3$

The vertex of the equation is (-1,3) so the axis is x=-1 and the correct option is 2.

(4)

The given equation is,

$y=x^2+4x+7$

To make perfect square add $(\frac{b}{2a})^2$ , i.e., $2^2$ .

$f(x)=x^2+4x+4+7-4$

$f(x)=(x+2)^2+3$

Therefore, the correct option is 4.

(5)

The given equation is,

$h=-16t^2+672t$

It can be written as,

$h=-16(t^2-42t)$

It is a downward parabola. so the maximum height of the function is on its vertex.

The x coordinate of the vertex is,

$x=\frac{b}{2a}$

$x=\frac{42}{2}$

$x=21$

Therefore, after 21 seconds the projectile reach its maximum height and the correct option is first.

(6)

The given equation is,

$f(x)=3x^3-12x^2-15x$

$f(x)=3x(x^2-4x-5)$

Use factoring method to find the factors of the equation.

$f(x)=3x(x^2-5x+x-5)$

$f(x)=3x(x(x-5)+1(x-5))$

$f(x)=3x(x-5)(x+1)$

Equate each factor equal to 0.

$x=0,-1,5$

Therefore, the zeros of the given equation is 0, -1, 5 and the correct option is 2.

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3 years ago

PLEse help graph the function

Andrews [41]

Answer:

2+2=4-1=3 quick mafs everyday mans on da block, smoke trees

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3 years ago