Respuesta :

3.14(a2 + ab) 
=3.14(4^2 + 4*2)
=3.14(16+8)
=3.14(24)
=75.36

Evaluating the expression, 3.14(a² + ab) = 75.36

Substitution

Substitution is a system for solving system of equation. It simply implies to put in place of another.

Therefore, let's evaluate the expression 3.14(a² + ab) using substitution method. Where a = 4 and b = 2

Therefore,

3.14(4² + 4(2)) = 3.14(16 + 8)

3.14(16 + 8) = 3.14(24)

3.14(24) = 75.36

learn more on direct substitution here: https://brainly.com/question/2859039

Otras preguntas