Question

Find the solutions to the equation (check all that apply) x2+14x+48=0.
a.x=4
b.x=-8
c.x=6
d.x=-2
e.x=3
f.x=-6

Answer 1

You can either plug in each of the values (a-f) in as x and see if you get 0 on the left...

Answer 2

...or you can factor x^2+14x+48 and see what you get.

Answer 3

i'd suggest factoring. do you know how to do that?

Answer 4

like foiling?

Answer 5

could you just help

Answer 6

it's FOIL in reverse.

Answer 7

your factored answer is going to look like (x + a)(x + b)...
you just need to find the numbers a and b.

if you foil (x +a)(x + b) out, you get x^2 +(a + b)x + ab...

Answer 8

so to match what you have, you need two numbers that multiply to 48 but add to 14.

Answer 9

I know and I did it and i cant find a solution i just plugged everything in and i still dont have a solution

Answer 10

what two numbers multiply to 48 but add to 14?

Answer 11

8 & 6\

Answer 12

good. so a and b are 8 and 6.

so you have (x + 8)(x + 6) = 0 as your factored form.

Answer 13

now, if a * b = 0, then either a=0 or b=0.

Answer 14

you have (x + 8) * (x + 6) = 0

so, either x+8 = 0 or x+6 = 0.

Solve each of these for x and you get your two answers.

Answer 15

x^2+14x+48 = 0
x^2+6x+8x+48 = 0 [48=6*8 and 6+8 =14(middle term)]
x(x+6)+8(x+6)=0 [taking x common]
(x+6)*(x+8)=0
now x=-6 or x=-8; ANS
Both the values satisfy equation x^2+14x+48=0.

Answer 16

Thank you!