The answer is B. Parabola is a symmetrical open plane bend framed by the crossing point of a cone with a plane parallel to its side. The way of a shot affected by gravity in a perfect world takes after a bend of this shape.
Step 1: Subtract -2 from both sides.<span><span><span><span>
m2</span>+<span>4m</span></span>−<span>(<span>−2</span>)</span></span>=<span><span>−2</span>−<span>(<span>−2</span>)</span></span></span><span><span><span><span>
m2</span>+<span>4m</span></span>+2</span>=0</span>
Step 2: Use quadratic formula with a=1, b=4, c=2.<span>
m=<span><span><span>−b</span>±<span>√<span><span>b2</span>−<span><span>4a</span>c</span></span></span></span><span>2a</span></span></span><span>
m=<span><span><span>−<span>(4)</span></span>±<span>√<span><span><span>(4)</span>2</span>−<span><span>4<span>(1)</span></span><span>(2)</span></span></span></span></span><span>2<span>(1)</span></span></span></span><span>
m=<span><span><span>−4</span>±<span>√8</span></span>2</span></span><span><span>
m=<span><span>−2</span>+<span><span><span>√2</span><span> or </span></span>m</span></span></span>=<span><span>−2</span>−<span>√2</span></span></span><span>
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Answer:
Which i think is the first one, there may just be a typing error.
Step-by-step explanation:
A polynomial of order n has the following format:

In which a is the leading coefficient,
are the roots.
If a root appears m times, they are said to have multiplicity m.
Leading coefficient of 1 and roots 21 and 31 with multiplicity 1

So the correct answer is:

Which i think is the first one, there may just be a typing error.
L=16
W=21
Set up a systems of equations:
x=length
y=width
xy=336
x+5=y
Use substitution to solve:
x(x+5)=336
x^2+5x=336
Solve using factoring:
x^2+5x-336=0
(x-16)(x+21)=0
x=16 and x= -21
Since length can't be negative, l=16
To find width, plug length into the first equation:
(16)y=336
y=21
So...
L=16
<span>W=21</span>