##### Solve using the perfect square method: x^2 6x = 7

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Solve using the perfect square method: x^2 + 6x = 7

May 18th, 2015

According to given question

x^2+6x=7

take half of 6, which is 3, and square it = 9. Add 9 to both sides
x^2 + 6x +9 = 7 + 9....left side is now first binomial
(x+3)^2 = 16..............take square root of both sides
x+3 = +/- 4
two solutions
x = 1
x = -7

May 18th, 2015
thank you for answering my question. what hapens to the 6x and the 9 though
May 18th, 2015

By completing the formula of (a+b)^2

a^2+b^2+2ab

according to question

x^2+2(x)(3)+9

May 18th, 2015

now you can understand easily with this example

May 18th, 2015
thank you
May 18th, 2015
I have one more qestion for you. Given the trinomial answer the questions below: x^2 + 2x + 1 = 0 a) Find the discriminant. b) Determine the number and type of solutions. c) Solve the equation. Show your answer in radical form.
May 18th, 2015

ok

May 18th, 2015

x^2+2x+1=0

The discriminant is just b^2-4*a*c with a polynomial ax^2 + bx + c = 0.

Therefore the discriminant is:

D = 2^2 - 4*1*1
D = 4 - 4
D = 0.
The discriminant is therefore zero.

x^2+2x+1=0

(x+1)^2=0

BY taking sqare root on both sides

x+1=0

x=-1

May 18th, 2015
Ok so how do I solve part b) Determine the number and type of solutions.
May 19th, 2015

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May 18th, 2015
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May 18th, 2015
Sep 24th, 2017
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