Answer:
A) 
Step-by-step explanation:
Point-slope formula.

Given.
Slope (m) = 3
Points (x, y) = (2, 1)
Easy
the easiest way is to imagine that you have a rectangle with a corner cut off
the area of the figure=area of rectangle-area cut off
area that was cut off was a triangle
area of rectangle=length times width
area of triangle=1/2base times height
so we draw imaginary lines like in attachment
find area of rectangle
legnth=9 inch
width=9 inch
area=9 times 9=81 in^2
triangle
the top part is ?+5=9, so the base of triangle=4
the side is ?+4=9, so the base is 5
area=1/2 times 4 times 5=10 in^2
area=rectangle-triangle
area=81-10=71 in^2
Answer:
x = -3
Step-by-step explanation:
simplify
3(x - 4) = -21
3x - 12 = -21
3x = = -9
x = -3
Ok if you show me the question I can try to help but you got to show it
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