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50 POINTS! (I rlly need help)

(ALGEBRA 1)

50 POINTS! (I rlly need help) (ALGEBRA 1)-example-1
User Nefarion
by
7.3k points

1 Answer

6 votes

Answer:

43.06 ft

3.20 seconds

Explanation:

h = -16t^2 +50t +4

The maximum is at the vertex

The x coordinate for the vertex is a the axis of symmetry

The axis of symmetry is

h=-b/2a when the equation is at^2 +bt+c

h = -50/2(-16)

=-50/-32

= 1.5625

The maximum is when x is at 1.5625

to find y we put this into the equation

h = -16(1.5623)^2 + 50(1.5625) +4

= -16(2.44140625) + 78.125+4

= -39.0625+78.125+4

=43.0625

To the nearest hundredth

43.06 ft


The second part is to find when it hits the ground, or when h=0

0 = -16t^2 +50t +4

Using the quadratic formula

-b±sqrt(b^2 -4ac)

------------------------

2a

-50±sqrt(50^2 -4*-16*4)

------------------------

2*-16

-50±sqrt(2500 +256)

------------------------

-32

-50±sqrt(2756)

------------------------

-32

-50 + sqrt(2756) or -50 + sqrt(2756)

----------------------- -----------------------

-32 -32

-.078 3.20

Since time cannot be negative

3.20 seconds

User Klenwell
by
8.0k points