How do you solve -10x + y = 0 and 5x + 3y = -7?
1 Answer
Explanation:
Your starting system of equations looks like this
#{(-10x + y = 0), (5x + 3y = -7):}#
Multiply the second equation by
#{(-10x + y = 0), (10x + 6y = -14):}#
If you add these equations by adding the left-hand side and the right-hand side separately, you can eliminate the
The resulting equation will only have one unknown,
#{(-10x + y = 0), (10x + 6y = -14):}#
#stackrel("-------------------------------------------")#
#-color(red)(cancel(color(black)(10x))) + y + color(red)(cancel(color(black)(10x))) + 6y = 0 + (-14)#
#7y = -14 implies y = (-14)/7 = color(green)(-2)#
Pick one of the original equations and substitute
#-10x + (-2) = 0#
#-10x = 2 implies x = color(green)(-1/5)#