Answer:
x=10
Step-by-step explanation:
9x-40 and 3x+20 are corresponding angles ,so they have the same value or are equal to each other.
9x-40=3x+20 (equate the values to each other
9x-3x=40+20 (group like terms and solve)
6x=60 (divide both sides by six to make x be alone)
6x/6 = 60/6 (solve)
x=10
