Please help I’m completely stuck

Two numbers have a sum of -19. one number is x. what expression represents the other number?

Find the circumference of a pizza with a diameter of 10 inches round to the nearest tenth

Use the linear combination method to solve the system of equations. explain each step of your solution. if steps are not explained, you will not receive credit for that step. 2 + 9 = −26 −3 − 7 = 13