Because this is a fourth degree that will be tricky to factor as it is, we will do a u substitution. Let . We can now rewrite that polynomial in terms of u:
. Filling into the quadratic formula we have
. Simplifying down
and
or
. That means that u = 8 or u = -1. But don't forget that we let
, so we have to put x-squared back in for u. That gives us
which simplifies down to
. That also gives us
. When we take the square root of -1, we have to use the fact that -1 = i^2, so we sub that in to get
. All in all, your solutions are as follows:
which is choice b.
Tim and Tom are trying to earn money to buy a new game system over a 3-month period. Tim saved $45.38 each month. If they need a
1 answer:
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Given dimensions of a rectangular garden are:
length = 2(x+6) feet
width = 3.5x feet
using the distributive property on length we get, length = 2x+12
Perimeter of a rectangle is 2(length+width)
So, P = 2(2x+12+3.5x)
Solving it we get,
P = 2(5.5x +12) ..............adding like terms
P = .............multiplying and adding
P = 11x+24
So, perimeter is 11x+24 feet. This value of fencing will be needed.