Question

find the solutions to the system
y=x^2 + 5x +6
y=-4x+12

Answer 1

solving them simultaneously , eliminating y
x^2 +5x+6 = -4x+12

this is a quadratic in x, can you solve this ?

Answer 2

when i try i come up with the wrong awnser

Answer 3

what values of x you got ?

Answer 4

2,20 and -3,0

Answer 5

x^2 +5x+6 = -4x+12

x^2+9x -6 = 0
and 2,-3 are certainly not the solutions for x

can you try to solve
x^2+9x -6 = 0
again ?

are you sure question is correct ?as there are no integer solutions for x here

Answer 6

like the awnser choices are
2,-20 and -3,0
2,20 and -3, -18
-2,-20 and -3,-18
no soultions
so i guse i should pick D?

Answer 7

if the question is correct, then yes, D it is.....

Answer 8

but i'd say even D is not correct
if D was 'no integral solution' , then that would be correct

Answer 9

no the four in y=4x+12 is positive not negative

Answer 10

ohh!

so, the quadratic becomes
x^2 +x -6 = 0

this is easy to solve, can you ?

Answer 11

i can't say that i can

Answer 12

2 numbers with sum +1 and product = -6 are ... ?

Answer 13

-2 + 3?

Answer 14

yes

so we split x as +3x-2x

x^2+3x-2x -6
x (x+3) - 2 (x+3)

can you further factor out x+3 ?

Answer 15

no because it is an odd number?

Answer 16

you can factor out that term
\((x+3)(x-2\))

Answer 17

how?

Answer 18

because that term was common in both the terms! :)

Answer 19

so that would be the awnser ?

Answer 20

so, x = 2,-3

Answer 21

and since y = 4x+12

find y when x= 2
find y when x= -3

Answer 22

thanks bro