Question

y^2-18y+81=16

Answer 1

y^2 - 18y + 81 - 16 = 0

y^2 - 18y + 65 = 0

you can solve that using the formula now

Answer 2

y - 9 = 4
y = 13

Answer 3

how did you get that pratu043?

Answer 4

how did you get 65? Im sorry i dont understand how to do any of it.

Answer 5

ok well to get the equation = 0

whatever number is after '=' should be brought to the other side of the '=' and will change the sign of it e.g. if it is = +65 bringing it to the other side of the = will give you -65 =

Answer 6

so all we do is y^2-18y+81=16

bring 16 to the other side which will give you -16

and you will get y^2-18y+81- 16 = 0

you work that out and you will be left with

y^2 - 18y + 65 = 0

Answer 7

\[(x-9)^2=16\]
\[x-9=\pm 4\]
\[x-9=4\]
\[x=13\]
\[x-9=-4\]
\[x=5\]

Answer 8

22,14?

Answer 9

I tend to use the formula to work it out
do you know the formula ?

Answer 10

(x+c)^2

Answer 11

13, 5 is that right?

Answer 12

yes it is

Answer 13

do you know about the formula to solve quadratic equations?

Answer 14

thanks! i guess it just take a little bit more of explaining for me to understand lol

Answer 15

we have been studying different ones, and I read over them and its just hard for me to get, math is not my best interest at all

Answer 16

you can use a formula if you like, but this is a set up for a complete square, since
\[x^2-18x+81=(x-9)^2\] and
\[16=4^2\]

Answer 17

how do you do the fraction sign i will write out the formula you might recognise it

Answer 18

fraction sign??

Answer 19

found it one minute

Answer 20

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

Answer 21

and you need to know the values of a, b and c to use this formula
which is why we re write the equation so it = 0

it should be in the format of

\[ax ^{2} + bx + c = 0\]

Answer 22

thats why i had written \[y ^{2} - 18y + 65 = 0\]

Answer 23

ok yea i know that one, i guess it threw me off for a min when you said fraction, i was thinking a regular fraction. i did one of those problems earlier..ooh it only took me like 15 minutes to figure it out lol

Answer 24

where the values are

\[a = 1 \]
which is the same as \[y^{2}\]

Answer 25

b = -18

Answer 26

and c = 65

Answer 27

lol hope I helped instead of confusing you more :p

Answer 28

theres no way to confuse me when im already confused lol but it does help out alot, ive fallen waaay beind in this class and I just dont think im gonna pass it. i dont look for just the answers on here, i have to have it explained to me cause i wont never get it if i just get told the answer