Problem

Solve for x 4/7+3/x=(2x+1)/(7x)

The given problem is an algebraic equation where the variable x appears in both the numerator and denominator of fractions. The equation is set up as a proportion, involving a sum on one side and a single fraction on the other side. The task is to find the value of x that makes both sides of the equation equal. This typically involves finding a common denominator, combining like terms, and then isolating the variable x to solve for it.

47+3x=2x+17x

Answer

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Solution:

Step:1

Isolate terms with x on one side of the equation.

Step:1.1

Subtract 47 from both sides: 3x=2x+17x47

Step:1.2

Simplify the equation.

Step:1.2.1

Divide 2x+17x into two parts: 3x=2x7x+17x47

Step:1.2.2

Reduce fractions by canceling x.

Step:1.2.2.1

Eliminate x where possible: 3x=27+17x47

Step:1.2.2.2

Rewrite the equation: 3x=27+17x47

Step:1.3

Combine like terms over a common denominator: 3x=247+17x

Step:1.4

Subtract 4 from 2: 3x=27+17x

Step:1.5

Place the negative sign in front: 3x=27+17x

Step:2

Determine the least common denominator (LCD) of the equation.

Step:2.1

The LCD is the least common multiple (LCM) of the denominators: x,7,7x

Step:2.2

To find the LCM, separate the process for numbers and variables: LCM of 1,7,7 and LCM of x1,x1.

Step:2.3

LCM is the smallest number divisible by all numbers: List prime factors and multiply the highest power of each.

Step:2.4

The number 1 is not prime.

Step:2.5

Since 7 is prime, it remains unchanged.

Step:2.6

The LCM of 1,7,7 is 7.

Step:2.7

The variable x1 simplifies to x.

Step:2.8

The LCM of x1,x1 is x.

Step:2.9

Combine the numeric and variable parts for the LCD: 7x

Step:3

Eliminate fractions by multiplying each term by the LCD, 7x.

Step:3.1

Multiply the equation by 7x: 3x(7x)=27(7x)+17x(7x)

Step:3.2

Simplify the left side.

Step:3.2.1

Use the commutative property: 73xx=27(7x)+17x(7x)

Step:3.2.2

Multiply 7 and 3x: 21xx=27(7x)+17x(7x)

Step:3.2.3

Cancel x: 21=27(7x)+17x(7x)

Step:3.3

Simplify the right side.

Step:3.3.1

Simplify each term.

Step:3.3.1.1

Cancel 7: 21=2x+17x(7x)

Step:3.3.1.2

Use the commutative property: 21=2x+717xx

Step:3.3.1.3

Cancel 7: 21=2x+1xx

Step:3.3.1.4

Cancel x: 21=2x+1

Step:4

Solve for x.

Step:4.1

Rearrange the equation: 2x+1=21

Step:4.2

Isolate x-terms.

Step:4.2.1

Subtract 1 from both sides: 2x=211

Step:4.2.2

Calculate the result: 2x=20

Step:4.3

Divide by 2 to solve for x.

Step:4.3.1

Divide each term by 2: 2x2=202

Step:4.3.2

Simplify the left side: x=202

Step:4.3.3

Simplify the right side: x=10

Knowledge Notes:

  1. Isolating Variables: When solving for a variable, it's common to isolate terms containing the variable on one side of the equation.

  2. Simplifying Fractions: Fractions can be simplified by canceling out common factors in the numerator and denominator.

  3. Least Common Denominator (LCD): The LCD of several fractions is the least common multiple (LCM) of their denominators. It's used to combine fractions or eliminate them from an equation.

  4. Prime Numbers: A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. Prime factorization helps in finding the LCM.

  5. Commutative Property of Multiplication: This property states that the order in which two numbers are multiplied does not affect the product.

  6. Solving Linear Equations: Linear equations are solved by performing operations that maintain the equality, such as adding, subtracting, multiplying, or dividing both sides by the same number.

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