It looks like you have a math problem involving equations and statements in Ukrainian. Let's break it down:

Task 1: Checking the validity of statements

• a) $-3 + (-7) = 10$
• b) $-10 + 4 = -6$
• c) $3 - 4 = 1$
• d) $-12 + 15 = -3$

Task 2: Finding the sum of the numbers $2 + 4$ on the coordinate plane.

Task 3: Completing the sentences

• a) The sum of two positive numbers is a number...
• b) Out of two numbers with different signs, the greater one is...
• c) Out of two numbers $-4, 2$ and $-5,3$, the one with the smaller modulus is...
• d) The number $-5$ is a number opposite to...

I can help you with solving these! Do you want me to go through each step, or would you like a specific part explained first?