N(2x+y) = x +1
Differentiate both sides, using the Chain Rule on the left side.
(1 / (2x + y)) * d(2x + y)/dx = 1
(1 / (2x + y)) * (2 + dy/dx) = 1
<span>Rearrange to isolate dy/dx.
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Answer:
x = 11
Step-by-step explanation:
From the diagram, we find,
(2x - 16) + (x - 8) = 9
=> 2x - 16 + x - 8 = 9
=> 2x + x - 16 - 8 = 9
=> 3x - 24 = 9
=> 3x = 9 + 24
=> 3x = 33
=> x = 33/3
=> x = 11
X + 5y = 1 . . . . (1)
8x - 2y = 3 . . . .(2)
Solution 1.
From (1), x = 1 - 5y
substituting for x in (2), we have:
8(1 - 5y) - 2y = 3
8 - 40y - 2y = 3
8 - 42y = 3
42y = 5
y = 5/42
x = 1 - 5(5/42) = 1 - 25/42 = 17/42.
Solution 2.
Multiply (1) by 8, to get:
8x + 40y = 8 . . . . . (3)
(3) - (2) = 40y - (-2y) = 8 - 3
42y = 5
y = 5/42
substitute for y into (3), to get:
8x + 40(5/42) = 8
8x + 100/21 = 8
8x = 8 - 100/21 = 68/21
x = (68/21)/8 = 17/42
If 1/5 can for 1 (each) room, then:
for 51 rooms, (51*1/5)=10.2 rooms.
Round to nearest whole number since you can't just paint 0.2 of a room: answer = 10
