1) 9x + 2 = x + 5 ---> 9x + 2 = 6
subtracted X from one side but not the other
2) 3(x-4) + 5 = 12 ---> 3x + 4 + 5 = 12
didn't distribute correctly: 3(x-4)
multiplied the X by 3 but not the -4
Answer:

area: 136 cm
perimeter: 48 cm
Step-by-step explanation:
For the first one just subtract

for the second one you just have to break it into smaller, more digestible pieces (work below)
The greatest common factor of 18 and 42 would be 2.
Answer:
[see below]
Step-by-step explanation:
Finding the slope of the two points:

The slope is -6.
Using an incomplete slope-intercept form equation to find the y-intercept:

The equation for the line passing the points is
.
The equation in standard from would be
.
Answer:
ASA
Step-by-step explanation:
you know 2 angles and a side so ASA