Answer: m∠6=18
3x-15=x+7
add 15 to both sides
3x-15+15=x+7+15
3x=x+7+15
3x=x+22
subtract x from both sides
3x-x=x+22-x
3x-x=22
2x=22
divide both sides by 2
2x÷2=22÷2
x=22÷2
x=11
plug it into the equation
11+7=18
m∠6=18
I hope this is good enough:
