Answer:
Breadth = 8 cm
Length = 17 cm
Step-by-step explanation:
Given rectangle:
Breadth = x cm
Length = x + 9 cm
Area = length * breadth
= x * (x + 9)
= x² + 9x
Rectangle with length and breadth increased:
Breadth = x + 3 cm
Length = x + 9 + 3 = x + 12 cm
Area = 84 + (x² + 9x) cm²
(x +3) * (x +12) = 84 + x² + 9x
Use FOIL method
x*x + x*12 + 3*x + 3*12 = 84 + x² + 9x
x² + 12x + 3x + 36 = 84 + x² + 9x {add the like terms}
x² + 15x + 36 = 84 + x² + 9x
x² + 15x + 36 - 84 - x² - 9x = 0
6x - 48 = 0
6x = 48
x = 48/6
x = 8
Breadth = x = 8 cm
Length = x + 9 = 8 +9 = 17 cm
(4×20)+(4×9)=80+36=116
this is the <span>distributive property
I hope this helped!!!:)</span>
Answer:
68% degree percent
Step-by-step explanation:
68% degree percent
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)
I think the answer is for A the explanation is that x represent the amount of time or second that you spend in an elevator and y represent the numbers of floors that the building have.