SOLUTION: A square is represented by 4x^2 +28x+49 inches squared. Find the length of a side of the square in terms of x ( I need to set this up in equation format and solve.)

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Question 113291This question is from textbook Beginning and Intermediate Algebra
: A square is represented by 4x^2 +28x+49 inches squared. Find the length of a side of the square in terms of x
( I need to set this up in equation format and solve.)
This question is from textbook Beginning and Intermediate Algebra

Found 2 solutions by Earlsdon, MathLover1:
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
You are given the area of the square as:
A+=+4x%5E2%2B28x%2B49 and, as you know, the area of a square is A+=+s%5E2 where s is the length of one side of the square, so...
s%5E2+=+4x%5E2%2B28x%2B49
Let's factor the trinomial to see if it's a perfect square:
4x%5E2%2B28x%2B49+=+%282x%2B7%29%282x%2B7%29=%282x%2B7%29%5E2 it is a perfect square, so...
s%5E2+=+%282x%2B7%29%5E2 Now take the square root of both sides.
s+=+%282x%2B7%29 and this is the length of one side of the square in terms of x.

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

4x%5E2+%2B+28x+%2B+49+=+0
You have:
a+=+4
b+=+28
c+=+49
Use the square root formula and find roots:
x%5B1%2C2%5D=%28-b+%2B-+sqrt+%28b%5E2+-4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29
x%5B1%2C2%5D=%28-28+%2B-+sqrt+%2828%5E2+-4%2A4%2A49+%29%29+%2F+%282%2A4%29

x%5B1%2C2%5D=%28-28+%2B-+sqrt+%28784+-+784%29%29+%2F+8

x%5B1%2C2%5D=%28-28+%2B-+sqrt+%280%29%29+%2F+8
x%5B1%5D=%28-28+%2B-+0%29%2F8………..there is only one solution
x%5B1%5D+=+-+3.5