2 x - 5y = 13
2 × -1 - 5 × -3 = 13
Answer:
(-1, -3)
For x = 4, then it means 3 to the fourth power or 3 times 3 times 3 times 3 times 3. 3^4 = 81 and 8 times that is 648.
y(x) = 8 * 3^x where x = 4:
y(x) = 8 * 3^4 = 8 * 81
y(x) = 648
The Function Rule then being that for every value of x there is one and only one value of y. y is the dependent variable and x is the independent variable.
Answer:
The time(s) the ball is higher than the building: Interval (0,4)
Step-by-step explanation:
s(t)=-16t^2+64t+400
Determine the time(s) the ball is higher than the building:
s(t)>400
-16t^2+64t+400>400
Subtracting 400 both sides on the inequality:
-16t^2+64t+400-400>400-400
-16t^2+64t>0
Multiplying the inequality by -1:
(-1)(-16t^2+64t>0)
16t^2-64t<0
Fatorizing: Comon factor 16t:
16t(16t^2/16t-64t/16t)<0
16t(t-4)<0
t is greater than zero:
t>0→t-4<0→t-4+4<0+4→t<4
Then t>0 ant t<4:
Solution = (0, Infinite) ∩ (-Infinite, 4)
Solution = (0,4)