Solve the system of equations -12x-5y=40 12x-11y=80

The answer is (-5/24, -7.5).

Step-by-step explanation:

There are two methods to solving a system of equations - substitution or elimination.  In this example, we can use elimination since the coefficients of 'x' are opposite signs.  To complete elmination, we simply add the equations together:

-12x - 5y = 40

+ 12x - 11y = 80

-16y = 120

Use inverse operations to solve for 'y' by dividing both sides by -16 to get       y = -7.5.

Next, plug in the value of 'y' into one of the equations and solve for 'x':

-12x  - (5)(-7.5) = 40 or  -12x + 37.5 = 40, now subtract 37.5 from both sides:  -12x + 37.5 - 37.5 = 40 - 37.5 or -12x = 5/2.  Lastly, divide both sides by -12 to solve for x, x = -5/24.  

answer is 144

step-by-step explanation: