Final answer:
To solve a system of equations using subtraction, you want to eliminate one variable by multiplying one or both of the equations by a constant so that the coefficients of either x or y will cancel out when the equations are subtracted. Follow the steps outlined above to solve each system of equations and find their solutions.
Step-by-step explanation:
To solve a system of equations using subtraction, you want to eliminate one variable by multiplying one or both of the equations by a constant so that the coefficients of either x or y will cancel out when the equations are subtracted.
Let's solve each system of equations using subtraction:
a. 2x + 3y = 7 and 3x + 2y = 4
Multiplying the first equation by 2 and the second equation by 3 gives us:
4x + 6y = 14 and 9x + 6y = 12
Subtracting the second equation from the first equation eliminates the y variable:
(4x + 6y) - (9x + 6y) = 14 - 12
-5x = 2
Dividing both sides by -5 gives us:
x = -2/5
Now we can substitute this value of x into one of the original equations to solve for y:
2(-2/5) + 3y = 7
-4/5 + 3y = 7
3y = 35/5 + 4/5
3y = 39/5
y = 13/5
So the solution to the system of equations is x = -2/5 and y = 13/5.