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HELP PLZ
Solve each proportion for the variable ​

HELP PLZ Solve each proportion for the variable ​-example-1
User Melessia
by
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1 Answer

12 votes

Answer:

x = -1

Explanation:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

4/12-((x+2)/(2*x+5))=0

x + 2

Simplify ——————

2x + 5

1

Simplify again

3

1 (x + 2)

— - ————— = 0

3 2x + 5

Find the Least Common Multiple

The left denominator is : 3

The right denominator is : 2x+5

Number of times each prime factor

appears in the factorization of:

Prime

Factor Left

Denominator Right

Denominator L.C.M = Max

{Left , Right}

3 1 0 1

Product of all

Prime Factors 3 1 3

Number of times each Algebraic Factor

appears in the factorization of:

Algebraic

Factor Left

Denominator Right

Denominator L.C.M = Max

{Left , Right}

2x+5 0 1 1

Least Common Multiple:

3 • (2x+5)

Denote the Least Common Multiple by L.C.M

Denote the Left Multiplier by Left_M

Denote the Right Multiplier by Right_M

Denote the Left Deniminator by L_Deno

Denote the Right Multiplier by R_Deno

Left_M = L.C.M / L_Deno = 2x+5

Right_M = L.C.M / R_Deno = 3

Two fractions are called equivalent if they have the same numeric value.

For example : 1/2 and 2/4 are equivalent, y/(y+1)2 and (y2+y)/(y+1)3 are equivalent as well.

To calculate equivalent fraction , multiply the Numerator of each fraction, by its respective Multiplier.

L. Mult. • L. Num. 2x+5

—————————— = ——————————

L.C.M 3 • (2x+5)

R. Mult. • R. Num. (x+2) • 3

—————————— = ——————————

L.C.M 3 • (2x+5)

Add the two equivalent fractions which now have a common denominator . Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

2x + 5 - ((x + 2) • 3) -x - 1

——————————— = —————————

3 • (2x + 5) 3 • (2x + 5)

Pull out like factors :

-x - 1 = -1 • (x + 1)

-x - 1

—————————— = 0

3 • (2x + 5)

Where a fraction equals zero, its numerator, the part which is above the fraction line, must equal zero.

Now, to get rid of the denominator, multiply both sides of the equation by the denominator.

-x - 1

——————— • 3 • (2x + 5) = 0 • 3 • (2x + 5)

3 • (2x + 5)

Now, on the left hand side, the 3 • 2x + 5 cancels out the denominator, while, on the right hand side, zero times anything is still zero.

The equation now takes the shape :

-x - 1 = 0

Solving a Single Variable Equation:

Solve : -x - 1 = 0

Add 1 to both sides of the equation :

-x = 1

Multiply both sides of the equation by (-1) : x = -1

User Dragonmnl
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