Question

x²-3x-10=0 need really fast help

Answer 1

Pls tell me two factors of -10 so that their sum is -3.

Answer 2

5 and 2 one negatve one positive

Answer 3

-5 and 2

Answer 4

yup good:)
Nw -3x can be written as -5x+2x. Agree?

Answer 5

yes

Answer 6

good:)
\(x^2-3x-10=0\)
\(x^2-5x+2x-10=0\)
what do u get when u factorise \(x^2-5x\)?

Answer 7

ughhhhhh im stuck lol

Answer 8

\(x^2-5x=x*x-5*x\)
What is common to both \(x^2\) and \(5x\)?

Answer 9

x

Answer 10

good:) nw when u take it out what remains

Answer 11

x-5

Answer 12

aj?

Answer 13

ya. right:)
So
\(x^2-5x=x(x-5)\)
Nw can u factorise
2x-10

Answer 14

x-5

Answer 15

well
2x-10=2(x-5)
Nw can u factorise
x(x-5)+2(x-5)

Answer 16

@kittenbalm

Answer 17

ugh how do i foil?

Answer 18

treat (x-5) as one term. for simplicity let us assume (x-5)=y.
xy+2y. can u factorise this?

Answer 19

yes you can

Answer 20

I was asking whether u can? I can

Answer 21

oh no

Answer 22

xy+2y
What is common to both xy and 2y?

Answer 23

y

Answer 24

good:)
So what remains when u take it out?

Answer 25

x+2

Answer 26

right:)
xy+2y=y(x+2)
our y=x-5.
so
x(x-5)+2(x-5)=(x-5)(x+2)
\(x^2-3x-10=0\)
\(x^2-5x+2x-10=0\)
\(x(x-5)+2(x-5)=0\)
\((x-5)(x+2)=0\)
x-5=0 or x+2=0
Hope u can find the two values of x nw:)

Answer 27

-5 and 2

Answer 28

Nope. pls check again:)

Answer 29

oh 5 and -2

Answer 30

yup good:)