Solve the system equation

3x-4y=40
5x-5y=55

1 answer

To solve the system of equations:

3x - 4y = 40 --------(1)
5x - 5y = 55 --------(2)

We can use the method of substitution or the method of elimination.

Using the method of substitution:

From equation (1), we solve for x in terms of y:
3x = 40 + 4y
x = (40/3) + (4/3)y

Substituting this expression for x into equation (2), we get:
5(40/3 + (4/3)y) - 5y = 55

Multiplying through by 3 to clear the fraction:
200 + 20y - 15y = 165

Simplifying:
5y = -35
y = -7

Now we substitute this value of y into equation (1) to solve for x:
3x - 4(-7) = 40
3x + 28 = 40
3x = 12
x = 4

Therefore, the solution to the system of equations is x = 4 and y = -7.