Quadratics easy question. Please help

1.62 seconds

Step-by-step explanation:

h = -16t² + 24t + 16.4

The initial height is 16.4 feet.  The snowboarder lands 3.2 feet below this, or at a height of 13.2 feet.

13.2 = -16t² + 24t + 16.4

16t² − 24t − 3.2 = 0

Solve with quadratic formula:

t = [ -(-24) ± √((-24)² − 4(16)(-3.2)) ] / 2(16)

t = [ 24 ± √(576 + 204.8) ] / 32

t = 1.62

The snowboarder is in the air for 1.62 seconds.

here you hope this .

step-by-step explanation:

hypotenuse = √(15² + 8²)

=  √(225 +64)

=  √(289) = 17

sin(x) = cos(y) = 8/17

they are identical so long as you are doing the sine of one angle and the cosine of the only other angle that isn't the right angle.

d. bc = 12 and ef = 16

step-by-step explanation:

we are given that δabc : δdef such that .

also, it is given that

so, from the options, we need that .

a.

b.

c.  

d.

as, we can see that only option d gives the same ratio as i.e. .

hence, the possible lengths are bc = 12 and ef = 16.