We know that m<JKL = m<JKM + m<MKL
Let's substitute the values from the picture into our equation above.
10x - 11 = 43 + 8x - 20
Combine like terms.
10x - 11 = 8x + 23
Subtract 8x from both sides and add 11 to both sides.
2x = 34
Divide both sides by 2
x = 17
m<MKL = 8x - 20 = 8(17) - 20 = 136 - 20 = 116 degrees.
m<JKL = 10x - 11 = 10(17) - 11 = 170 - 11 = 159 degrees.