Answer:
A' (-1, 2)
Step-by-step explanation:
(x, y) -> (-y, x)
A' (-1, 2)
B' (1, -2)
C' (2, -2)
D' (0, -2)
The area of the ceiling:
A = 14² = 196 ft²
We need plaster to cover 196 ft².
196 : 90 = 2.17778
Answer: We have to buy 3 pails of plaster.
If it is on sane for 25% off, that's the same as being on sale for 75% of the original price.
Multiply the original cost by 75% in decimal form.
30*.75=22.5
Final answer: $22.50
The equation of the line is (slope-intercept) y=

x+(-7) or (standard form)

x+y=-7