Question

Solve by graphing. x2 + 2x – 3 = 0

Answer 1

Well if you have a calculator you could certainly graph it. But just factor it instead! No need for the quadratic formula here.

Answer 2

please help

Answer 3

I assume you have to graph this by hand, so get out a sheet of paper (if you haven't already) and start plotting points. I suggest using only integers as x since your answer will be an integer. The answer should become clear as you graph one point at a time

Answer 4

so what do you need help with? are you selecting one of those graphs?

Answer 5

yes

Answer 6

Can you eliminate any of them as being impossible?

Answer 7

Check your answer. Do the values of x beside the third graph make the equation true?

Answer 8

I don't think so

Answer 9

Oh I see the problem. The third graph is right, but the x-values beside it are wrong.

Answer 10

it would be -1,3 so is that right when I plugged that it for x I didn't get 0 but I might not be doing it right

Answer 11

no it would be 1,-3

Answer 12

so 1*1=1+
2*-3=-6 -
3=0 but it doesn't it equals -9

Answer 13

none of them are going to be equal to 0 as far as I can tell

Answer 14

\[x ^{2}+2x-3=0\] test x=1,-1,3,-3\[1*1+2-3=3-3=0\]\[(-1*-1)-2-3=-1-3=-4\]\[3*3+6-3=12\]\[(-3*-3)-6-3=9-9=0\]

Answer 15

I'll help you with the factor :)
(x+3)* (x-1) = 0. This means that x is 0 at -3, and at 1.
Which plots have x being 0 at -3 and at 1?
That leaves us graphs A & C. We know the function is positive so that leaves C as the correct answer.

Answer 16

You are so welcome.