The equation equivalent to x + 8 = 21 is (x + 8)
4 = 21
4 (Option B), which maintains the same solution by multiplying both sides by 4.
To find an equivalent equation to x + 8 = 21, you can perform the same operation on both sides. Option B, (x + 8)
4 = 21
4, is equivalent because it multiplies both sides by 4.
This results in 4x + 32 = 84, which maintains the same solution as the original equation. Options A and C involve different operations on each side, making them non-equivalent. In equation-solving, it's crucial to apply the same operations symmetrically to maintain equality.
Therefore, the correct choice is B, providing an equivalent equation that preserves the relationship between x and 8 while modifying both sides by the same factor.
The complete question is:
Which equation is equivalent to x+8=21？
A. (x+8)* 4=21
B. (x+8)* 4=21* 4
C. (x+8)* 4=21* 2