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Solve, using cross - multiplication : ...

Solve, using cross - multiplication :
3x + 4y = 11
2x + 3y = 8

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To solve the system of equations using cross multiplication, we have the equations: 1. \(3x + 4y = 11\) (Equation 1) 2. \(2x + 3y = 8\) (Equation 2) ### Step 1: Rewrite the equations in standard form We can rewrite the equations in the form \(Ax + By + C = 0\): 1. \(3x + 4y - 11 = 0\) (Here, \(a_1 = 3\), \(b_1 = 4\), \(c_1 = -11\)) 2. \(2x + 3y - 8 = 0\) (Here, \(a_2 = 2\), \(b_2 = 3\), \(c_2 = -8\)) ### Step 2: Identify coefficients From the equations, we have: - \(a_1 = 3\), \(b_1 = 4\), \(c_1 = -11\) - \(a_2 = 2\), \(b_2 = 3\), \(c_2 = -8\) ### Step 3: Set up the cross multiplication formula The cross multiplication formula is given by: \[ \frac{x}{b_1c_2 - b_2c_1} = \frac{y}{c_1a_2 - c_2a_1} = \frac{1}{a_1b_2 - a_2b_1} \] ### Step 4: Calculate the determinants 1. For \(b_1c_2 - b_2c_1\): \[ b_1c_2 - b_2c_1 = 4 \cdot (-8) - 3 \cdot (-11) = -32 + 33 = 1 \] 2. For \(c_1a_2 - c_2a_1\): \[ c_1a_2 - c_2a_1 = (-11) \cdot 2 - (-8) \cdot 3 = -22 + 24 = 2 \] 3. For \(a_1b_2 - a_2b_1\): \[ a_1b_2 - a_2b_1 = 3 \cdot 3 - 2 \cdot 4 = 9 - 8 = 1 \] ### Step 5: Substitute into the cross multiplication formula Now we can substitute these values into the formula: \[ \frac{x}{1} = \frac{y}{2} = \frac{1}{1} \] ### Step 6: Solve for \(x\) and \(y\) From the above equations, we have: 1. \(x = 1\) 2. \(\frac{y}{2} = 1 \implies y = 2\) ### Final Solution Thus, the solution to the system of equations is: \[ x = 1, \quad y = 2 \]
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