Are these correct? If not help me please??

no, no, yes, no, yes, yes

Step-by-step explanation:

x + 1, 2x, these are not equivalent

no

10x, 5(x+5)

5(x+5) distribute the 5 to get 5(x+5) = 5x + 25

5x + 25 is not equal to 10x, so no

no

1 + 2x = 2x + 1, these are equivalent since the constant and coefficients are the same

yes

2x, 2x - 5, these are not equivalent since once has a constant of -5 while the other does not

no

15x -1, 3(x+4x) - (3-2)

3(x+4x) - (3-2) combine like terms

3(5x) - (1) multiply through parentheses

= 15x -1

so 15x - 1 = 3(x+4x) - (3-2), these are equivalent

yes

1/2 * (4x-2),2x-1

1/2 * (4x-2) multiply through parentheses to get

2x - 1

so these two are equivalent

yes

452,489 to the nearest thousand is 452,000

probably .5

i can on others if necessary.