Geno started with the expression [tex]\(90 - (18 + -2)(-3)\)[/tex].
1. He first needs to simplify within the parentheses:
[tex]\[
18 + -2 = 16
\][/tex]
2. Substitute this result back into the expression:
[tex]\[
90 - 16(-3)
\][/tex]
3. Next, perform the multiplication:
[tex]\[
16 \times -3 = -48
\][/tex]
4. Substitute this result back into the expression:
[tex]\[
90 - (-48)
\][/tex]
5. Simplify the expression by remembering that subtracting a negative is equivalent to adding the positive counterpart:
[tex]\[
90 + 48
\][/tex]
6. Finally, perform the addition:
[tex]\[
90 + 48 = 138
\][/tex]
So, the final result of the expression [tex]\(90 - (18 + -2)(-3)\)[/tex] is:
[tex]\[
138
\][/tex]
The interim result during the calculation of the multiplication within the parentheses was:
[tex]\[
-48
\][/tex]
Therefore, the complete solution is:
[tex]\[
\begin{array}{l}
90-(18+-2)(-3) \\
90-(16)(-3) \\
90 - (-48) \\
90 + 48 \\
138
\end{array}
\][/tex]
