Respuesta :
The skier earns 35.875 points.
We can find the height in the air by using -b/2a:
-28/2(-16) = -28/-32 = 0.875
This will give the skier 0.875 points.
To find the amount of time in the air, we solve the related equation:
0=-16t²+28t+8
We will first factor out the GCF, -4:
0=-4(4t²-7t-2)
Now we will factor the trinomial in parentheses using grouping. We want factors of 4(-2)=-8 that sum to -7; -8(1) = -8 and -8+1=-7. This is how we will "split up" bx:
0=-4(4t²-8t+1t-2)
Now we will group the first two and last two terms:
0=-4[(4t²-8t)+(1t-2)]
We will factor out the GCF of each group:
0=-4[4t(t-2)+1(t-2)]
This gives us the factored form:
0=-4(4t+1)(t-2)
Using the zero product property, we know that either t-2=0 or 4t+1=0:
t-2=0
t-2+2=0+2
t=2
4t+1=0
4t+1-1=0-1
4t=-1
4t/4 = -1/4
t=-1/4
Negative time makes no sense, so t=2. This gives the skier 5(2) = 10 points.
Counting the perfect landing, we have 25+10+0.875 = 35.875 points.
We can find the height in the air by using -b/2a:
-28/2(-16) = -28/-32 = 0.875
This will give the skier 0.875 points.
To find the amount of time in the air, we solve the related equation:
0=-16t²+28t+8
We will first factor out the GCF, -4:
0=-4(4t²-7t-2)
Now we will factor the trinomial in parentheses using grouping. We want factors of 4(-2)=-8 that sum to -7; -8(1) = -8 and -8+1=-7. This is how we will "split up" bx:
0=-4(4t²-8t+1t-2)
Now we will group the first two and last two terms:
0=-4[(4t²-8t)+(1t-2)]
We will factor out the GCF of each group:
0=-4[4t(t-2)+1(t-2)]
This gives us the factored form:
0=-4(4t+1)(t-2)
Using the zero product property, we know that either t-2=0 or 4t+1=0:
t-2=0
t-2+2=0+2
t=2
4t+1=0
4t+1-1=0-1
4t=-1
4t/4 = -1/4
t=-1/4
Negative time makes no sense, so t=2. This gives the skier 5(2) = 10 points.
Counting the perfect landing, we have 25+10+0.875 = 35.875 points.
Answer:
35.875 points.
Step-by-step explanation:
Lots of math I'm too lazy to put on here buh bye
