Ricardo throws a stone off a bridge into a river below. The stone's height (in meters above the water), xxx seconds after Ricardo threw it, is modeled by

w(x)=-5(x-8)(x+4)w(x)=−5(x−8)(x+4 )w, left parenthesis, x, right parenthesis, equals, minus, 5, left parenthesis, x, minus, 8, right parenthesis, left parenthesis, x, plus, 4, right parenthesis

What is the maximum height that the stone will reach?

Khan Academy

correct choice is a

step-by-step explanation:

the equation of the line passing through the points and is

thus, the equation of the line that passes through the points (0, -6) and (-3, 0) is

it is impossible.

a and c

for infinitely many solutions we require both left and right sides to be equal

distribute and simplify

a

14 - 8x = 20 - 8x - 6 = 14 - 8x ← both sides equal so infinite solutions

b

6x - 54 = 6x - 54 + x = 7x - 54 ← not equal

c

4x + 16 = 4x + 10 + 6 = 4x + 16 ← both sides equal so infinite solutions

d

5x - 40 + 10 = 5x + 10

5x - 30 = 5x + 10 ← not equal

answer is c chief it always is