Final answer:
The equivalent expression for 2/3 - 4/5 is 2/3 + (-4/5), which is changing the subtraction into an addition by taking the opposite sign of the second term.
Step-by-step explanation:
The student's question asks for an equivalent expression for the mathematical expression 2/3 - 4/5. When we look at subtraction in mathematics, we often convert it into an addition problem by changing the sign of the number being subtracted and then proceeding with addition following the rules for addition of integers. Therefore, when we subtract 4/5 from 2/3, it is equivalent to adding the opposite of 4/5 to 2/3, which is adding -4/5. Following this rule of sign change, the equivalent expression for 2/3 - 4/5 is 2/3 + (-4/5), which is represented as option B. This is similar to the given example where subtracting -6 from 2 is the same as adding 6, resulting in 2+6 = 8.