Two fifths of the senior class earned a grade of B+ or higher on an advanced mathematics exam. If 42 seniors scored at least a B
2 answers:
You might be interested in
Answer:
h(x) = -16x² + 192x + 208
784ft
6 sec
13 sec
Step-by-step explanation:
a)
h(x) = -16x² +vx + h
here v represent velocity
represent initial height of launch
h(x) = -16x² + 192x + 208
b)
h(x) = -16x² + 192x + 208
here a = -16
b = 192
c = 208
x = -b/2a
= -192/2(-16)
= 6
plug this value in the equation
h(x) = -16(6)² + 192(6) + 208
= 784ft
e)
Plug h(x)=0 in the equation
0 = -16x² + 192x + 208
divide equation by -16
x² - 12x - 13 = 0
Factors
1x * -13x = -13
1x - 13x = -12
Factorised form
x² - 12x - 13 = 0
x² + x - 13x - 13 = 0
x(x+1) -13(x+1) = 0
(x+1)(x-13) = 0
x = -1
x = 13
Since time can not be negative so we will reject x = -1