We must find the value of x. By the definition of a rectangle, we know that NJKM has four right angles. Therefore, the measure of m ∠ NJK is 90.
m ∠ NJK=90
With the Angle Addition Postulate we can express m ∠ NJK as a sum of m ∠ NJM and m ∠ KJM.
m ∠ NJM + m ∠ KJM = m ∠ NJM
⇕
m ∠ NJM + m ∠ KJM = 90
We are given that m ∠ NJM =2x-3 and m ∠ KJM=x+5. We will substitute these expressions into our equation.
2x-3 + x+5 = 90
Let's solve it!
