Final answer:
By setting up an equation based on the property that linear pairs sum up to 180 degrees, we conclude that mll equals 43 degrees after solving for x and substituting back into the expression.
Step-by-step explanation:
We are given two angles adjacent to each other: mll which is (x + 10)°, and mlp which is (2x + 71)°. Since these two angles form a linear pair, their sum must be 180° because they form a straight line. We can write and solve the equation x + 10 + 2x + 71 = 180 to find the value of x.
Combining like terms gives us 3x + 81 = 180. Subtracting 81 from both sides gives us 3x = 99. Dividing both sides by 3 we find that x = 33. Now we can substitute x back into the expression for mll which is (x + 10)° to find the measure of mll. Therefore, mll = (33 + 10)° = 43°.