2x+5y=55

9x-2y=3
solve (round to nearest hundreth)

1 answer

To solve the system of equations:

  1. \( 2x + 5y = 55 \) (Equation 1)
  2. \( 9x - 2y = 3 \) (Equation 2)

We can use the substitution or elimination method. I will use the substitution method.

Step 1: Solve Equation 1 for \( y \)

From Equation 1:

\[ 5y = 55 - 2x \]

\[ y = \frac{55 - 2x}{5} \]

Step 2: Substitute \( y \) in Equation 2

Now, substitute the expression for \( y \) into Equation 2:

\[ 9x - 2\left(\frac{55 - 2x}{5}\right) = 3 \]

Step 3: Simplify the equation

Multiply both sides by 5 to eliminate the fraction:

\[ 5(9x) - 2(55 - 2x) = 15 \]

\[ 45x - 110 + 4x = 15 \]

Combine like terms:

\[ 49x - 110 = 15 \]

Step 4: Solve for \( x \)

Add 110 to both sides:

\[ 49x = 125 \]

Now, divide by 49:

\[ x = \frac{125}{49} \approx 2.55 \text{ (rounded to nearest hundredth)} \]

Step 5: Substitute \( x \) back to find \( y \)

Now substitute \( x \) back into the equation for \( y \):

\[ y = \frac{55 - 2\left(\frac{125}{49}\right)}{5} \]

Calculate \( 2 \times \frac{125}{49} \):

\[ 2 \times \frac{125}{49} = \frac{250}{49} \]

Now substitute back into the equation for \( y \):

\[ y = \frac{55 - \frac{250}{49}}{5} \]

Converting 55 to a fraction:

\[ 55 = \frac{2695}{49} \]

Now we have:

\[ y = \frac{\frac{2695 - 250}{49}}{5} \]

Calculate \( 2695 - 250 = 2445 \):

\[ y = \frac{\frac{2445}{49}}{5} = \frac{2445}{245} \]

Now we divide:

\[ y = \frac{2445 \div 245}{1} \approx 9.98 \text{ (rounded to nearest hundredth)} \]

Final Result

The solution to the system of equations is approximately:

\[ x \approx 2.55, \quad y \approx 9.98 \]