Problem
(3) \( 2 x+15=43-5 x \) (4) \( 3+4 x=9 x+13 \)
Solution
Step 1 ：\( 2x+15=43-5x \) → \( 7x = 28 \) → \( x = 4 \)
Step 2 ：\( 3+4x=9x+13 \) → \( 5x = -10 \) → \( x = -\frac{10}{3} \)
Step 1 ：\( 2x+15=43-5x \) → \( 7x = 28 \) → \( x = 4 \)
Step 2 ：\( 3+4x=9x+13 \) → \( 5x = -10 \) → \( x = -\frac{10}{3} \)
