Question

find k 49x^2-70x+k

Answer 1

is that the complete q

Answer 2

yes

Answer 3

may i know from which topic is this from ?

Answer 4

it just tells me to find k
for 49x^2-70x+k

Answer 5

from factoring

Answer 6

its a quadratic and has a constant k,
wat does it mean to find k simply ? there should be some context to it... when it asks

Answer 7

oh ok, i think you need to find k such that the quadratic becomes factorable

Answer 8

revealing some more info about the problem wil help

Answer 9

hold on let me see..

Answer 10

okay !

Answer 11

it says find the integral value pf k that makes 49x^2-70x+k a perfect square trinomial, and express the result in factored form

Answer 12

@rsadhvika

Answer 13

ohk now that makes sense :)

Answer 14

you need to find k such that you can express

49x^2-70x+k

as

(ax+b)^2

Answer 15

lets try to complete the square,
you familiar wid completing the square ?

Answer 16

it's new to me

Answer 17

okay its easy concept lets see

Answer 18

you remember the formula

\(a^2 + 2ab + b^2 = (a+b)^2\)

?

Answer 19

we're going to use that formula

Answer 20

ok yes

Answer 21

\(49x^2-70x+k \)

\(7^2x^2-2*30*x+k \)

\((7x)^2-2*30*x+k \)

Answer 22

fine so far ?

Answer 23

yes

Answer 24

compare it wid the formula above, wats missing ?

Answer 25

\(a^2+2ab + \color{red}{b^2} = (a+b)^2\)

Answer 26

we dont have \(\color{red}{b^2}\) to complete the square right ?

Answer 27

in place of \(\color{red}{b^2}\) , we just have \(k\)

so to complete the square, \(k = \color{red}{b^2} = 35^2\)

Answer 28

below is the correct equation :-


\((7x)^2-2*35*x+k\)

Answer 29

so if when k = 35^2,

\((7x)^2-2*35*x+35^2 \)

\((7x-35)^2\)

Answer 30

it becomes a perfect square triinomial like above