To find the number that plus 0.35 equals -1.43, you can set up the equation:
\[ x + 0.35 = -1.43 \]
Now, to solve for \( x \), subtract 0.35 from both sides:
\[ x = -1.43 - 0.35 \]
Now, perform the subtraction:
\[ x = -1.78 \]
So, the answer is \( -1.78 \).