Question

Graph the equation y = x2 - 3x -4. For what value or values of x is y = 0

Answer 1

This is asking for the solutions to the quadratic because the solutions are where y = 0. Set y = 0.
\[0 = x^2 - 3x - 4\]Can you factor this?

Answer 2

x2 messing me up is it just x+x-3x-4

Answer 3

No. \[x^2 = x \times x\]

Answer 4

What 2 factors of -4 add up to -3?

Answer 5

-4+1

Answer 6

Alright. Place the factors into their positions.
\[x^2 - 3x - 4 = 0\implies (x - 4)(x + 1) = 0\]Now, remember how 0 times anything equals 0?

Answer 7

4

Answer 8

Alright. That's one value. x = 4.
Now do the same for the other part.
x + 1 = 0
x = ?

Answer 9

sorry this is times so I'm super stressed

Answer 10

No problem.
x = 4, -1
For those values, y is equal to 0.

Answer 11

thank you so much for walking me through it

Answer 12

np :)