Question

what is the value of x??
(2x+14)(x+14)=952

Answer 1

FOIL:
2x^2+2(14x)+14x+196=2x^2+42x+196=952
2x^2+42x-756=x^2+21x-378=0
can you use the quadratic formula from here? 'cause I don't want to...

Answer 2

\[x=(-b \pm \sqrt{b^2-4ac})/2a\]

Answer 3

(2x-14)(x-14)=9522
2(x-7)(x-14)=9522
(x-7)(x-14)=4761

Answer 4

where \[ax^2+bx+c=0\] is the form
so plug in
a=1
b=21
c=-378
into the formula above and simplify

Answer 5

wow you guys are math wizs:)

Answer 6

it's just algebra :)

Answer 7

@ unk
dude i think you messed up and forgot about the -4761, check your answer.

Answer 8

a=1
b=21
c=-378
\[x=(-21 \pm \sqrt{21^2-4(1)(-378)})/2=(-21 \pm \sqrt{1953)}/2\]

Answer 9

\[=(-21 \pm 3\sqrt{217})/2=(3/2)(-7 \pm \sqrt{217)}\]

Answer 10

so\[x=\left\{ (3/2)(-7-\sqrt{217},(3/2)(-7+\sqrt{217)} \right\}\] is what I got

Answer 11

whoops

Answer 12

am I right? or did I mess up too? this one was long and annoying :(

Answer 13

im gonna try on on paper instead of in my head...

Answer 14

@ alexandraox3 I think my answer is the right one.