Consider the given equation is 
and one of the 6 in the options is -6.
Given:
The equation is
To find:
The value of x.
Solution:
We have,
Subtracting 3 from both sides, we get
Divide both sides by -2.
Therefore, the value of x is -6.
3 to the power of 5
you multiply 3 times 5 instead of 3 times 3 times 3 times 3 times 3
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He equation of a parabola is x = -4(y-1)^2. What is the equation of the directrix?
<span>You may write the equation as </span>
<span>(y-1)^2 = (1) (x+4) </span>
<span>(y-k)^2 = 4p(x-h), where (h,k) is the vertex </span>
<span>4p=1 </span>
<span>p=1/4 </span>
<span>k=1 </span>
<span>h=-4 </span>
<span>The directrix is a vertical line x= h-p </span>
<span>x = -4-1/4 </span>
<span>x=-17/4 </span>
<span>------------------------------- </span>
<span>What is the focal length of the parabola with equation y - 4 = 1/8x^2 </span>
<span>(x-0)^2 = 8(y-4) </span>
<span>The vertex is (0,4) </span>
<span>4p=8 </span>
<span>p=2 (focal length) -- distance between vertex and the focus </span>
<span>------------------------------- </span>
<span>(y-0)^2 = (4/3) (x-7) </span>
<span>vertex = (7,0) </span>
<span>4p=4/3 </span>
<span>p=1/3 </span>
<span>focus : (h+p,k) </span>
<span>(7+1/3, 0)</span>
