Expand the expression $4\left(t+6\right)$4(t+6).

A student incorrectly used the distributive property and wrote $7\left(4x+3\right)=28x+3$7(4x+3)=28x+3.

Which of the following is the best explanation to help the student correct their error?

Expand the expression $3\left(6+r\right)$3(6+r).

Expand the expression $\left(r+3\right)\times5$(r+3)×5.

Multiply a polynomial by a monomial involving the same variable using a variety of tools