1. **Simplify the expression:** $5x - 70 + 13x + 65$ Combine like terms (terms with $x$ and constants separately): $$5x + 13x - 70 + 65 = (5 + 13)x + (-70 + 65) = 18x - 5$$ 2. **State the problem:** Simplify the algebraic expression $5x - 70 + 13x + 65$. 3. **Formula used:** Combine like terms by adding coefficients of $x$ and constants separately. 4. **Intermediate work:** $$5x - 70 + 13x + 65 = 5x + 13x - 70 + 65$$ $$= \cancel{5x} + \cancel{13x} - 70 + 65$$ $$= 18x - 5$$ 5. **Final answer:** $$\boxed{18x - 5}$$ This is the simplified form of the given expression.