10 miles 45 miles
----------------- * --------------------- Cross Multiply
16 kilometres x kilometres
10 x = 720
x = about 72 kilometres
Parabola form : (y-k) = a(x-h)², where h and k are the vertex(h , k)
The vertex is given (2 , - 9), the equation of the parabola becomes:
y+9 = a(x-2)²
But we know this curve passes through (5, - 18)
Plug the respective values of x & y in the equation:
-18 +9 = a(5-2)² → - 9 = 9a & a = -9/9 and a= - 1
It isn't A because there isn't a decimal in the hundredths.
It isn't B because it doesn't have a decimal coefficient on the left side: that means it could be C or D, to find out we should find what x is in C:
0.5x-5=0.15x+2
0.5x=0.15x+7
0.35x=7
Divide both sides by 7
0.05x=1
Now multiply both sides by 20:
x=20
That means it must be D, let's make sure:
0.6x-3=0.28x+5
0.6=0.28x+8
0.32x=8
Divide both sides by 8:
0.04x=1
Now multiply both sides by 25:
x=25
So the answer is D
Hope this helps :)
Answer:
Step-by-step explanation:
18 degrees
