Question

give two examples that show how using parentheses can change the order in which operations are performed in an expression.

Answer 1

1,
3 + 4 * 6 = 3 + 24 = 27    ( using PEMDAS  which says multiply before add))

To do the addition first we put parentheses around the 3 + 4:-

(3 + 4) * 6  = 7*6 = 42

2.
 6 + 8 / 4   = 6 + 2 = 8

If we put parentheses around the 6 and 8 :-

(6 + 8) / 4   
 = 14/4
= 3.5

Answer 2

Parenthesis indicate which part of the equation is to be done first, see PEMDAS. For example, 3(5-2)-4=5, but 3*5-(2-4)=17