What’s the correct answer for this

45 degrees

Step-by-step explanation:

The interior angles of a triangle add to 180 degrees.

<ABC + <BCA + <CBA = 180

We know <ABC is 90 degrees, and <BCA is 45, so we can substitute them in.

90+45+<CBA=180

Combine like terms by adding 90 and 45

135+<CBA=180

Subtract 130 on both sides to get the variable by itself

<CBA=45

-2

7 - 9 = -2

reversed:

-2 + 9 = 7