Use the method of substitution to solve the following system

Use the method of substitution to solve the following system of equations. If the system is dependent, express the solution set in terms of one of the variables. Leave all fractional answers in fraction form. 8x 5y 23 20

Solution

8x+5y =-23, 5x +5y =-20

5x +5y =-20 =>5y =-20-5x

put 5y =-20-5x in 8x+5y =-23

8x-20-5x =-23

8x-5x=-23+20

3x=-3

x=-1

x=-1,5y =-20-5x

5y =-20-5(-1)

5y =-20+5

5y =-15

y =-15/5

y =-3

consistent system

solution is (x,y)=(-1,-3)