Solve the System of Equations with Fractions: Find the Values of X and Y

Question

3x+3y=2 \frac{3}{x}+\frac{3}{y}=2

9x4y=7 \frac{9}{x}-\frac{4}{y}=-7

Video Solution

Step-by-Step Solution

To solve this system of linear equations, follow these steps:

  • Step 1: Examine and rearrange the first equation 3x+3y=2 \frac{3}{x} + \frac{3}{y} = 2 .
  • Step 2: Express one variable in terms of the other. We can isolate 3x\frac{3}{x} to get 3x=23y\frac{3}{x} = 2 - \frac{3}{y}.
  • Step 3: Substitute 3x=23y\frac{3}{x} = 2 - \frac{3}{y} into the second equation 9x4y=7\frac{9}{x} - \frac{4}{y} = -7.
  • Step 4: Replace 9x\frac{9}{x} with 3(23y)3\left(2 - \frac{3}{y}\right) leading to 3(23y)4y=73\left(2 - \frac{3}{y}\right) - \frac{4}{y} = -7.
  • Step 5: Simplify the equation: Distribute 33 into 23y2 - \frac{3}{y} to obtain (69y)4y=7(6 - \frac{9}{y}) - \frac{4}{y} = -7.
  • Step 6: Combine the terms to get 613y=76 - \frac{13}{y} = -7.
  • Step 7: Isolate 13y\frac{13}{y}: 13y=13\frac{13}{y} = 13.
  • Step 8: Solve for yy: Multiply both sides by yy, leading to 13=13y13 = 13y, hence y=1y = 1.
  • Step 9: Substitute y=1y = 1 back into 3x=23y\frac{3}{x} = 2 - \frac{3}{y}, resulting in 3x=23\frac{3}{x} = 2 - 3, or 3x=1\frac{3}{x} = -1.
  • Step 10: Solve for xx: Multiply both sides by xx, leading to 3=x3 = -x, thus x=3x = -3.

Therefore, the solution to the system of equations is x=3\boldsymbol{x = -3} and y=1\boldsymbol{y = 1}.

The correct choice among the given answer choices is the third option: x=3,y=1\boldsymbol{x = -3, y = 1}.

Answer

x=3,y=1 x=-3,y=1