What is the measure of angle 4?

45 degrees

Step-by-step explanation:

∠1 and ∠4 are on a straight line. Therefore, they are supplementary and add to 180 degrees.

∠1+∠4=180

We know that the m∠1 is 135 degrees. We can substitute 135 in for ∠1.

135+∠4=180

Now we have to solve for ∠4. To do this, we need to get ∠4 by itself. 135 is being added on to ∠4. To undo this, subtract 135 from both sides, because subtraction is the opposite of addition.

135-135+∠4=180-135

∠4=180-135

∠4=45

The measure of ∠4 is 45 degrees.

step-by-step explanation: 4 cause 2+2=4