Solve for X in the Fraction Equation: Isolate the Variable Step-by-Step

Question

Solve for X:

15(x+14)=710+35x25 -\frac{1}{5}(x+\frac{1}{4})=\frac{7}{10}+\frac{3}{5}x-\frac{2}{5}

Video Solution

Solution Steps

00:00 Find X
00:03 Open parentheses properly, multiply by each factor
00:20 Find the common denominator and multiply accordingly
00:52 Arrange the equation so that only the unknown X is on one side
01:07 Collect like terms
01:13 Isolate X
01:20 And this is the solution to the problem

Step-by-Step Solution

To solve this linear equation, we begin by simplifying it:

Step 1: Distribute the fraction on the left side of the equation.

  • We have 15(x+14)-\frac{1}{5}(x + \frac{1}{4}). Distribute the 15-\frac{1}{5}:
    15x1514=15x120 -\frac{1}{5} \cdot x - \frac{1}{5} \cdot \frac{1}{4} = -\frac{1}{5}x - \frac{1}{20} So, the equation becomes:
    15x120=710+35x25 -\frac{1}{5}x - \frac{1}{20} = \frac{7}{10} + \frac{3}{5}x - \frac{2}{5}

Step 2: Simplify the right side.

  • First, combine the constant terms 710\frac{7}{10} and 25-\frac{2}{5} on the right side:
    Convert 25-\frac{2}{5} to tenths to combine: 25=410-\frac{2}{5} = -\frac{4}{10}.
    Now, 710410=310\frac{7}{10} - \frac{4}{10} = \frac{3}{10}.
    The right side simplifies to:
    310+35x \frac{3}{10} + \frac{3}{5}x

Step 3: Move all terms involving x x to one side and constants to the other.

  • Add 15x\frac{1}{5}x to both sides:
    120=310+35x+15x -\frac{1}{20} = \frac{3}{10} + \frac{3}{5}x + \frac{1}{5}x
  • Combine like terms involving x x on the right side:
    Convert 15x\frac{1}{5}x to a common denominator with 35x\frac{3}{5}x which is 35x=610x \frac{3}{5}x = \frac{6}{10}x and 15x=210x\frac{1}{5}x = \frac{2}{10}x, giving us:
    810x \frac{8}{10}x , thus yielding
    310+810x \frac{3}{10} + \frac{8}{10}x
  • To isolate x x , subtract 310\frac{3}{10} from both sides:
    120310=810x -\frac{1}{20} - \frac{3}{10} = \frac{8}{10}x

Step 4: Solve the resulting equation for x x .

  • Calculate 120310-\frac{1}{20} - \frac{3}{10}:
    Convert 310-\frac{3}{10} to a common denominator with 120-\frac{1}{20}:
    310=620-\frac{3}{10} = -\frac{6}{20}.
    So, 120620=720-\frac{1}{20} - \frac{6}{20} = -\frac{7}{20}:
    The equation becomes:
    720=810x -\frac{7}{20} = \frac{8}{10}x
  • Divide both sides by 810\frac{8}{10} to solve for x x :
    x=(720)÷(810) x = \left(-\frac{7}{20}\right) \div \left(\frac{8}{10}\right)
  • When dividing fractions, invert the divisor and multiply:
    x=720×108 x = -\frac{7}{20} \times \frac{10}{8}
  • Simplify:
    x=7×1020×8=70160 x = -\frac{7 \times 10}{20 \times 8} = -\frac{70}{160}
  • Simplify further by dividing both numerator and denominator by the greatest common divisor (which is 10):
    x=716 x = -\frac{7}{16}

Therefore, the solution to the equation is x=716 x = -\frac{7}{16} .

The correct choice is:

716 -\frac{7}{16}

Answer

716 -\frac{7}{16}