1. Equivalent Expressions are written quantities that are equal.
To find equivalent expressions, it looks like you can just expand the second expression and then see if it matches the first.
2. So, expand 5(2x+3) using the distributive property.
5(2x+3) = 5×2x + 5×3 = 10x+15
It matches the first expression which means that they are equivalent.
I will also do 2-5 for you to check your work.
3. -2(-6+5) = 12-10 = 2 2 ≠ 12x-10
not equivalent
4. 3(4x+5) = 12x+15 12x+15 ≠ 12x-15
not equivalent
5. -(-4x-3) = 4x+3 4x+3 ≠ 4x-3
not equivalent