Answer:
middle term = 7x
Explanation:
in order to find the middle term, we will expand the bracket on the left hand side and compare the expressions on both sides.
(x + 2) (3x + 1) = 3x² + ___ + 2
let the unknown expression = y
(x + 2) (3x + 1) = 3x² + y + 2
Expanding the bracket on the left hand side by multiplication:
x + 2( 3x + 1) = (x × 3x) + (x × 1) + (2 × 3x) + ( 2 × 1)
= 3x² + x + 6x + 2
= 3x² + 7x + 2
Comparing with the expression on the right hand side:
3x² + 7x + 2 = 3x² + y + 2
∴ y = 7x
middle term = 7x