Answer:
The answer is C.
Step-by-step explanation:
Given formula h(t)=−16t2+v0t+h0 , where v0 is the initial velocity and h0 is the initial height.
In this case, the initial postion is a platform 30ft above ground so h0=+30
The initial velocity is 38 ft/s straight up into the air so v0=+38
h(t)=-16t2+38t+30
When the object hits the ground, h=0.
h=-16t2+38t+30=0
Simplifying 8t2-19t-15=0
(8t+5)(t-3)=0
t=-5/8 or 3
As time cannot be -ve, t=3s. The answer is C.
Answer:
$4,400.00
Step-by-step explanation:
20% of 4400 is 880.
Answer: In 4 minutes he will make 5 portraits
Step-by-step explanation:
Answer:
C y=1/2cos(x)-2
I'm not sure if it is right
My head hurts so its hard for me to concentrate
1. x^2 + 13x + 36 = 0
using powerful & time-sparing quadratic formula :
delta = 13^2 - 4*1*36 = 25 = 5^2
x1 and x2 = (-13 -/+ 5)/2 = -9 and -4
x^2 + 13x + 36 = (x+9)(x+4)
2. other way : complete the square
b^2 + 12b + 32 = b^2 + 2*6b + 6^2 - 6^2 + 32
b^2 + 12b + 32 = (b+6)^2 - 4
b^2 + 12b + 32 = (b+6-2)(b+6+2) = (b+4)(b+8)
3. other way : -4 "ovious" solution : (-4)^2 - (-4) -20 = 0
so the other is : -4 . a2 = -20/1 ---> a2 = 5
a^2 - a - 20 = (a-5)(a+4)
