### Home > CCA > Chapter 4 > Lesson 4.2.2 > Problem 4-53

4-53.

Rianna thinks that if *a* = *b* and if *c* = *d*, then *a* + *c* = *b* + *d*. Is she correct? Homework Help ✎

If you add the same amount to both sides of the equals sign, then the equation remains true.

Adding *c* to one side is the same as adding *d* to the other because *c* and *d* are equal.

Therefore, the equation (*a* + *c* = *b* + *d*) is correct.