Solve the Fractional System: 1/3x - 4y = 5 and x + 6y = 9

Question

Solve the above set of equations and choose the correct answer.

{13x4y=5x+6y=9 \begin{cases} \frac{1}{3}x-4y=5 \\ x+6y=9 \end{cases}

Video Solution

Step-by-Step Solution

To solve this system of equations, we are going to use the substitution method:

Given the equations:

{13x4y=5(Equation 1)x+6y=9(Equation 2) \begin{cases} \frac{1}{3}x - 4y = 5 \quad \text{(Equation 1)} \\ x + 6y = 9 \quad \text{(Equation 2)} \end{cases}

  • First, we solve Equation 2 for x x :

x=96y x = 9 - 6y

  • Substitute this expression for x x into Equation 1:

13(96y)4y=5 \frac{1}{3}(9 - 6y) - 4y = 5

Multiply through by 3 to eliminate fractions:

96y12y=15 9 - 6y - 12y = 15

Combine like terms:

918y=15 9 - 18y = 15

Subtract 9 from both sides:

18y=6 -18y = 6

Divide both sides by -18:

y=13 y = -\frac{1}{3}

  • Substitute y=13 y = -\frac{1}{3} back into the expression for x x from Equation 2:

x=96(13) x = 9 - 6(-\frac{1}{3})

x=9+2 x = 9 + 2

x=11 x = 11

Thus, the solution to the system of equations is:

x=11,y=13 x = 11, y = -\frac{1}{3} .

Answer

x=11,y=13 x=11,y=-\frac{1}{3}