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3 years ago

How would I solve this Rational Equation? Solve for all values of x.

Mathematics

1 answer:

Nesterboy [21]3 years ago

4 0

9514 1404 393

Answer:

x = 4

Step-by-step explanation:

I like to put these in the form f(x) = 0. We can do that by subtracting the right side. Common factors can be cancelled from numerator and denominator, provided they are not zero.

$\dfrac{7}{x+3}+\dfrac{3}{x-3}-\dfrac{x}{x-3}=0\\\\ \dfrac{7(x-3)+(x+3)(3-x)}{(x+3)(x-3)}=0\\\\\dfrac{(x-3)(4-x)}{(x-3)(x+3)}=0\\\\ \dfrac{4-x}{x+3}=0\qquad x\ne3\\\\x=4 \qquad\text{equate the numerator to zero, add $x$}$

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If you leave the numerator as (x-3)(4-x), then there are two values of x that make it zero. Because x=3 makes the equation "undefined", it cannot be considered to be a solution.

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Romashka [77]

The answer would be 28 square inches because you would multiple the length (4 inches) and the width (7 inches) to each other.

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3 years ago

Read 2 more answers

NGC is a hot air balloon in the sky from her spot on the ground. The angle of elevation from Angie to the balloon is 40°. If she

Goshia [24]

Answer:

The distance from hot air balloon to the ground $AC=50.1457 ft$ .

Step-by-step explanation:

Labelled diagram of given scenario is shown below.

Given that,

An angle of elevation of Hot air balloon by Angie is $40$ °.

When she stepped back $200 ft$ then angle of elevation was $10$ °.

Height of Angie is $5.5 ft$ .

To find: How far off the ground is a hot air balloon.

So, from figure

Height of Angie $(BC) = 5.5ft$

In triangle Δ $ABD$ ,

⇒ $tan {40\si {\degree}} = \frac{AB}{BD}$

⇒ $AB = tan (40) \times BD$ ....................(1)

Now, In triangle Δ $ABE$

⇒ $tan (10)= \frac{AB}{200+BD}$

⇒ $AB = tan(10)\times (200+BD)$

Here, substituting the value $AB$ from Equation (1) we get,

$tan(10)\times (200+BD)= tan(40)\times BD$

$tan(10)\times 200+tan(10)\times BD= tan(40)\times BD$

⇒ $BD\times (tan(40)-tan(10))=tan(10)\times 20$

⇒ $BD\times 0.6628 = 35.2654$

⇒ $BD = \frac{35.2654}{0.6628} =53.2067 ft$

Now, finding the value of $AB$ from equation (1)

$AB= tan(40)\times 53.2067=0.8391\times 53.2067$

$AB=44.6457 ft$

Therefore Length of $AC= AB+BC$ = $(44.6457 + 5.5) ft$

$AC=50.1457 ft$ .

Hence,

The distance from hot air balloon to the ground $AC=50.1457 ft$ .

6 0

3 years ago

A store sells Brazilian coffee for $10 per lb. and Columbian coffee for $14 per lb. If the store decides to make a 150-lb. blend

Artemon [7]

Answer:

The store should use 112.5 pounds of Brazilian coffee and 37.5 pounds of Colombian cofee.

Step-by-step explanation:

Let "b" be the amount of Brazilian coffee, in pounds, required for the blend and "c" the amount of Colombian coffee required, in pounds.

Since there are two unknown variables a two-equation system is needed to solve the problem, we can set up one equation for weight and another for price as follows:

$b+c=150\\10*b+14*c=11*150$