Can't figure the LCD?

Thank you everyone

2x + 2 = 2(x + 1); 4x + 4 = 4(x + 1).

LCD is 4x + 4, or 4(x + 1).

(As typed, though, the denominators are 2x and 4x; the LCD would be 4x).

Take care with presentation. I suspect that what you actually mean is :-

1/ (2x + 2) + 1/(4x+ 4)

1/ ( 2(x+ 1) ) + 1/ (4(x + 1))

2 + 1

----------

4(x+ 1)

3

--------

4( x + 1 )

Least common denominator. To make these expressions similar so that they can be dealt with the same (such as adding them together), the fractions need to have the same denominator. Factoring them can help find a multiple of each that is not too big.

2 is a prime number. 4 is the product of 2 • 2. Aha! We can use 4 as the LCD and just convert the fraction currently using 2. Multiply by the fractional equivalent of 1:

1/2x • 2/2 = 2/4x, making the first expression "2/4x+2".

I can't help you with LCD. I can fill you in on lsd though