Answer:
Step-by-step explanation:
<h3>A.</h3>
The equation for the model of the geyser is found by substituting the given upward velocity into the vertical motion model. The problem statement tells us v=69. We assume the height is measured from ground level, so c=0. Putting these values into the model gives ...
h(t) = -16t² +69t
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<h3>B.</h3>
The maximum height is at a time that is halfway between the zeros of the function.
h(t) = -16t(t -4.3125) . . . . . has zeros at t=0 and t=4.3125
The maximum height will occur at t=4.3125/2 = 2.15625 seconds. The height at that time is ...
h(t) = -16(2.15625)(2.15625 -4.3125) = 16(2.15625²) ≈ 74.39 . . . feet
The maximum height of the geyser is about 74.4 feet.
Step-by-step explanation:
they're is a neat little trick.
but first of all, "roots" means the 0 solutions of the equation. like
ax² + bx + c = 0
there are 2 solutions for x to make the whole expression equal 0.
these are the "roots".
now to the little trick :
when is a multiplication resulting in 0 ?
when at least one of the factors is 0.
and any quadratic expression can be written as multiplication of 2 factors. like
c(x - a)(x - b) = cx² - cax - cbx + cab
what are the "roots" or 0 points ?
either
c = 0
x - a = 0 | x = a
x - b = 0 | x = b
the leading coefficient = 3.
that means nothing else than c = 3.
root = 1 means (x - 1) is one factor.
root = -5 means (x + 5) is the other factor.
so, we have
3(x - 1)(x + 5) = 3x² + 12x - 15
and the equation is
3x² + 12x - 15 = 0
or
3x² + 12x = 15
To split this trinomial into two binomials, let's try and find two numbers which add to 6 and multiply to 8. To do this, we can list all the factors of 8 and then choose which factors also add to 6.
Factors of 8: (1, 8), (2, 4)
1 + 8 = 9, meaning that 1 and 8 are not the factors we are looking for. However, 2 and 4 do add to 6. By combining these numbers which an x (so that we can produce the 
term at the front of the trinomial), we find the binomials:
and 
The answer is x + 2 and x + 4.
Answer:
3ft 11 in
Step-by-step explanation:
1 foot equals 12 inches, 12 × 3 = 36 = 3 feet + 11 inches = 47 inches = 3ft 11in
