2c + 4d = 92
substitute the given values into the expression and evaluate
2c + 4d = (2 × 30) + (4 × 8) = 60 + 32 = 92
The answer is 92. First substitute in 30 for c and multiply it by 2, and you get 60. Then, substitute in 8 for d and multiply it by 4 to get 32. Add 60 + 32 and it equals 92.