For the second one....just multiply everything through by x (x + 1).....this leaves
2(x + 1) + 3x(x) = 2x + 5 simplify
2x + 2 + 3x^2 = 2x + 5 subtract 2x and 5 from both sides
3x^2 - 3 = 0 factor
3(x^2 -1) = 0 divide both sides by 3
x^2 - 1 = 0 factor again
(x + 1)(x - 1) = 0 set both factors to 0 and x = -1 and x = 1
Reject x = -1 (it makes two denominators in the original problem = 0)
So....x = 1 is the solution
Be sure and check this in the original problem........
a) The easiest way to do this one is just to cross-multiply......so we have
(2x -1)(x - 1) = (3x + 4)(x +7) expand both sides
2x^2 - 3x + 1 = 3x^2 + 25x + 28 subtract 2x^2 and 1 from both sides and add 3x to both sides
0 = x^2 + 28x + 27 factor
0 = (x + 27)(x + 1) setting both factors to 0, we have x = -1 and x = -27
Neither thing makes a denominator in the original problem = 0, so both solutions are good....
For the second one....just multiply everything through by x (x + 1).....this leaves
2(x + 1) + 3x(x) = 2x + 5 simplify
2x + 2 + 3x^2 = 2x + 5 subtract 2x and 5 from both sides
3x^2 - 3 = 0 factor
3(x^2 -1) = 0 divide both sides by 3
x^2 - 1 = 0 factor again
(x + 1)(x - 1) = 0 set both factors to 0 and x = -1 and x = 1
Reject x = -1 (it makes two denominators in the original problem = 0)
So....x = 1 is the solution
Be sure and check this in the original problem........