Question

Need help with option 1 or 2

Answer 1

Option 2.

1. Simplify 7 + (12 - 9) + 7 × 3(8 - 5)

According to the Order of Operations, contents of parentheses are evaluated first. This gives

... 7 + 3 + 7 × 3 × 3

Then multiplication and division are performed left to right.

... = 7 + 3 + 21 × 3

... = 7 + 3 + 63

Followed by addition and subtraction left to right.

... = 10 + 63

... = 73

A Google search box can be relied upon to do the operations in the correct order.

_____

2. When the expression is rewritten, a different result is obtained. This is because the operations indicated by the second set of parentheses are altered.

... (7 + 12) - 9 + (7 × 3)8 - 5

... = 19 - 9 + 21 × 8 - 5

... = 19 - 9 + 168 - 5

... = 10 + 168 - 5

... = 178 - 5

... = 173

In the first expression, both +8 and -5 are multiplied by 21. In the rewritten expression, only +8 is multiplied by 21.