Answer:
26 rows
Step-by-step explanation:
this is like a rectangle length×width situation.
seats per row = s
number of rows = r
s × r = 884
s = r + 8
so, we can use e.g. the second equation in the first :
(r + 8) × r = 884
r² + 8r = 884
r² + 8r - 884 = 0
the general solution to such a quadratic equation is
x = (-b ± sqrt(b² - 4ac))/(2a)
in our case
x = r
a = 1
b = 8
c = -884
r = (-8 ± sqrt(8² - 4×1×-884))/(2×1) =
= (-8 ± sqrt(64 + 3536))/2 = (-8 ± sqrt(3600))/2 =
= (-8 ± 60)/2 = -4 ± 30
r1 = -4 + 30 = 26
r2 = -4 - 30 = -34
a negative number did not make any sense for the number of rows, so r = 26 is our answer.
About 390 km because you drive 130 km per hour so 130 times 3 is 390
Answer:
y=-3x+14
Step-by-step explanation:
m=(y2-y1)/(x2-x1)
m=(-4-26)/(6-(-4))
m=-30/(6+4)
m=-30/10
m=-3
y-y1=m(x-x1)
y-26=-3(x-(-4))
y-26=-3(x+4)
y=-3x-12+26
y=-3x+14
