Find the values of x and y for the system: 7x−15y=27x - 15y = 2 and x + 2y=32y = 3

Answer: The solution to the system of equations is x=4929x = \frac{49}{29} and y=1929y = \frac{19}{29}.

Step-by-step solution

Step 1: Express one variable in terms of the other

From the second equation, x+2y=3x + 2y = 3, we can easily express xx in terms of yy. This is a common first step in the substitution method, where we isolate one variable to substitute it into the other equation. We achieve this by subtracting 2y2y from both sides of the equation.

Step 2: Substitute the expression into the other equation

Now, we substitute the expression for xx, which is 3−2y3 - 2y, into the first equation, 7x−15y=27x - 15y = 2. This substitution will result in a linear equation that contains only the variable yy, making it solvable.

Step 3: Simplify and solve for y

We first distribute the 7 into the parenthesis, which gives us 21−14y21 - 14y. Then, we combine the like terms, −14y-14y and −15y-15y, to get −29y-29y. Next, we subtract 21 from both sides of the equation and finally divide by −29-29 to find the value of yy.

Step 4: Substitute the value of y back into the expression for x

Now that we have the value of y=1929y = \frac{19}{29}, we substitute it back into the expression for xx that we derived in the first step: x=3−2yx = 3 - 2y. We multiply 2 by 1929\frac{19}{29} and then subtract the resulting fraction from 3, finding a common denominator to perform the subtraction.

Step 5: Verify the solution

To ensure our solution is correct, we substitute the calculated values of x=4929x = \frac{49}{29} and y=1929y = \frac{19}{29} into both original equations. If both equations hold true, our solution is verified. In this case, both equations are satisfied.

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