Question

x^2 - 14 x + 13 = 30 y
x^2 - 14 x = 30 y - 13
x^2 - 14 x + 49 = 30 y + 36 ****
(x-7)^2 = 30 y + 36
x - 7 = +/- sqrt (30 y + 36)
x = 7 +/- sqrt (30 y + 36)

where did you get the 49 or 36

Answer 1

I did it below after you asked

Answer 2

Here again:
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#

Completing the square
x^2 + a x = something
x^2 + a x + (a/2)^2 = something + (a/2)^2
so
if
x^2 -14 x = something
then
x^2 - 14 x +(14/2)^2 = something + (14/2)^2
or
x^2 - 14 x + 49 = something + 49
(x-7)^2 = something + 49
x - 7 = +/- sqrt (something + 49)

by taking half the second coefficient and squaring it, I get a perfect square.

# Math - Damon, Wednesday, April 23, 2008 at 10:13pm

and 49 - 13 = 36

Answer 3

which one is the the bottem or the top
number in exponents