Answer:
m∠1 = 144°
Explanation:
Step 1: Find the value of x:
Since angles 1 and 2 are supplementary, the sum of their measures equals 180°:
∠1 + ∠2 = 180
Thus, we can find x by substituting 7x + 18 for ∠1 and x + 18 for ∠2 in the equation above:
7x + 18 + x + 18 = 180
(8x + 36 = 180) - 36
(8x = 144) / 8
x = 18
Thus, x = 18.
Step 2: Find the measure of angle 1:
Now we can find the measure of angle 1 by substituting 18 for x in 7x + 18:
m∠1 = 7(18) + 18
m∠1 = 126 + 18
m∠1 = 144
Thus, the measure of angle 1 is 144°.