7y+2x=107y + 2x = 10 3y+7x=93y+7x=9 Find x and y

Answer: x=3343,y=5243x = \frac{33}{43}, \quad y = \frac{52}{43}

Step-by-step solution

Step 1: Multiply equations to align coefficients

We use the method of elimination to solve for the variables. To eliminate xx, multiply Equation (1) by 7 and Equation (2) by 2 so that both equations have the same coefficient, 14, for xx.

Step 2: Subtract the equations to solve for y

Subtract Equation (4) from Equation (3). The terms containing xx cancel out, leaving 43y=5243y = 52. Dividing both sides by 43 yields y=5243y = \frac{52}{43}.

Step 3: Substitute y into Equation (1) to solve for x

Now substitute the value y=5243y = \frac{52}{43} into the first equation, 2x+7y=102x + 7y = 10. Multiplying 7 by 52 gives 364, which gives 2x+36443=102x + \frac{364}{43} = 10.

Step 4: Isolate and solve for x

Convert 10 to a fraction with denominator 43, giving 43043\frac{430}{43}. Subtracting 36443\frac{364}{43} gives 2x=66432x = \frac{66}{43}. Dividing both sides by 2 yields x=3343x = \frac{33}{43}.

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