Question

Can anyone help me put the equation x^2=4-7x into the quadratic equation formula, please:)

Answer 1

might help to write it in ax^2 + bx + c = 0 format

Answer 2

Yeah I know that its like the first step

Answer 3

the quadratic formula is defined using the abc parts
\[x=\frac{1}{2a}(-b\pm\sqrt{b^2-4ac})\]

Answer 4

so, what do we have when it is in its ax^2 + bx + c = 0 format?

Answer 5

Plug it in

Answer 6

lets first see what you get when you work out the first step. unless of course youve got it from here

Answer 7

No I don't that's kind of the reason I am asking for help

Answer 8

this is the helping part :) we prefer that the askers participate in the solution process.

Answer 9

Yeah I got that

Answer 10

can you rearrange this into the ax^2 + bx + c = 0

x^2 = 4 -7x

Answer 11

0=-x^2-7x+4

Answer 12

thats pretty good

Answer 13

So it's wrong? or no?

Answer 14

its right enough :) i was expecting you to go the other way ... but its not wrong at all

so lets compare

ax^2 + bx + c = 0
-x^2 - 7x + 4 = 0

a= -1
b = -7
c = 4

Answer 15

Now you plug in the variables,k so lets move on.

Answer 16

\[x=\frac{1}{2a}(-b\pm\sqrt{b^2-4ac})\]
\[x=\frac{1}{2(-1)}(-(-7)\pm\sqrt{(-7)^2-4(-1)(4)})\]
\[x=-\frac{1}{2}(7\pm\sqrt{49+16})\]
etc ...