+864 Real numbers a and b satisfy
a + ab = 250
a - ab = -240
Enter all possible values of a, separated by commas.
+1790 We could isolate a from the first equation and get \(a=\frac{250}{1+b}\) before plugging it into the second equation, but let's do something simpler.
Adding the first and the secone equation, we get
\(2a=10\\ a=5\)
Plugging this in for b, we get
\(a=5,\:b=49\)
So, our final answer is 5.
Thanks! :)
*1200 points
+120 (a + ab) + (a - ab) ==> 250 + (-240)
2a ==> 10
a=5
solve it from here by plugging in a=5 into the equation. 
