14x^2-17x-6. (^being 14x squared)

Sagot :

factor?, if so
if in ax^2+bx+c form then
multiply a and c together
result=z,
find 2 numbers that multiply to get z and add up to get b
 so



14=a
-17=b
-6=c
14 times -6=-84
factor to find what 2 numbers add up to -17
-84=
-2, 42
-3,28
-4,21
-6,14
-7,12

add each up

-2, 42=40 nope
-3,28=25 nope
-4,21=17 yes, becase if -21 and 4 then answer
-6,14=8 nope
-7,12=5 nope

split up -17 into -21 and 4


14x^2-21x+4x-6
group
(14x^2-21x)+(4x-6)
undistribute
(7x)(2x-3)+(2)(2x-3)
revesres undistribute (ab+ac=a(b+c) or (a+b)(c)+(a+b)(d)=(a+b)(c+d))
(7x+2)(3x-3) is factore out form

then set it to zero and do th emath because if xy=0 then assume x and/or y=0 so
7x+2=0
subtract 2
7x=-2
divide by 7
x=-2/7

3x-3=0
add 3
3x=3
divide 3
x=1
x=-2/7 or 1