Answer:
b. 10
Explanation:
For the most part, these are problems in addition. The measures of the different angles add up according to the relationships given in the problem statement.
From the picture, you can tell that ∠JKN is the sum of ∠1 and ∠2, which are said to be equal (congruent). That is, ∠1 has a measure that is half of that of ∠JKN.
Since ∠JKN is a right angle, 90°, and the measure of ∠1 is half that, m∠1 is 45°.
So, to find t, we equate the given expression for m∠1 to 45 and solve.
4t +5 = 45
4t = 40 . . . . . subtract 5
t = 10 . . . . . . . divide by 4 . . . . . matches answer choice B