Question

Be certain you have solved for both variables in the system of equations. Solve the following systems of equations algebraically. Show your work. 5x-y=-5 3x-5y=-3

Answer 1

x= 1.27, y= 11.4 (to 3s.f.)

Explanation:

5x -y= -5 -----(1)

3x -5y= -3 -----(2)

From (1):

-y= -5x -5

divide by -1 throughout:

y= 5x +5 -----(3)

Subst. (3) into (2):

3x -5(5x +5)= -3

3x -25x +25= -3 (expand)

-22x= -3 -25

-22x= -28

divide by -22 throughout:

x= 1.2727 (5 s.f.)

x= 1.27 (3 s.f.)

subst. into (3):

y= 5(1.2727) +5

y= 11.4 (3 s.f.)