Answer:
a = 4
Step-by-step explanation:
y = 2x + 1 ......(1)
Going through y - y1 = m(x - x1)
m is slope and it is 2
y1 = 9 and x1 = a
y - 9 = 2(x - a)
y - 9 = 2x - 2a
y = 2x - 2a + 9 ........(2)
Equating (1) and (2)
2x + 1 = 2x - 2a + 9
Collecting like terms
2x - 2x + 2a = 9 - 1
2a = 8
a = 8/2
a = 4
Point are set up (x,y) you sub the number for x into the equation and see if you get the number for y.
y=4x+3
y=4 (5)+3
y=20+3
y=23
so A isn't the answer
y=4 (17)+3
y=68+3
y=71
B isn't the answer
y=4 (4)+3
y=16+3
y=19
and because 4 is the x value for c and d and there can only be 1 y value for each x you're answer is C because when x=4 y =19 or (4,19)
Capacity of the pool = 30 x 20 x 5 = 3000 ft³
Amount of water already filled = 30 x 20 x 4 = 2400 ft²
Amount of water needed to full the pool = 3000 - 2400 = 600 ft²
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Answer: 600 ft² of water is needed to fill up the pool.
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Answer:
20 Students :)
Step-by-step explanation:
