How do you solve the following system?: 5x + 2y =1 ,3x-7y=-125x+2y=1,3x−7y=−12
1 Answer
Mar 6, 2016
Explanation:
5 * x + 2 * y = 15⋅x+2⋅y=1
3 * x - 7 * y=-123⋅x−7⋅y=−12
Multiply the first equation by
17.5 * x + 7 * y = 3.517.5⋅x+7⋅y=3.5
3 * x - 7 * y=-123⋅x−7⋅y=−12
Add the two equations to get
20.5 * x + cancel(7y) - cancel(7y) = -8.5
x = -8.5/20.5 = -17/41
This means that you have
3 * (-17/41) - 7y = -12
y = (12 - 3 * 17/41)/7 = 63/41