x>7
Step-by-step explanation:
when dividing by a (-)
the inequality sign changes
Step-by-step explanation:
a) determine the rate in km/L
==> 9.5 L/100km = 10.526316 km/L
b) how far can the car travel with 475L petrol
==> 0.210526315789473km/l
c) how many litres of petrol do they need to travel 350 km
==>Liters per km (l/km)2.86×10-3
Liters per 10 km (l/10 km)0.03
Liters per 100 km (l/100km)0.29
Kilometer per liter (km/l)350
Answer:
z = x^3 +1
Step-by-step explanation:
Noting the squared term, it makes sense to substitute for that term:
z = x^3 +1
gives ...
16z^2 -22z -3 = 0 . . . . the quadratic you want
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<em>Solutions derived from that substitution</em>
Factoring gives ...
16z^2 -24z +2z -3 = 0
8z(2z -3) +1(2z -3) = 0
(8z +1)(2z -3) = 0
z = -1/8 or 3/2
Then we can find x:
x^3 +1 = -1/8
x^3 = -9/8 . . . . . subtract 1
x = (-1/2)∛9 . . . . . one of the real solutions
__
x^3 +1 = 3/2
x^3 = 1/2 = 4/8 . . . . . . subtract 1
x = (1/2)∛4 . . . . . . the other real solution
The complex solutions will be the two complex cube roots of -9/8 and the two complex cube roots of 1/2.
Answer:
f(x) = 4x − 12
Step-by-step explanation:
It's not quadratic. It's linear. Each time x increases by 1, f(x) increases by 4. So the slope is 4. The y-intercept (when x=0) is -12. The equation of the line is therefore:
f(x) = 4x − 12
