How do you do this simultaneous equation?

The y is the same for both equations. Equate them
-x - 5 = 2x + 4 Add x to both sides
- 5 = 3x + 4 Subtract 4 from both sides.
- 9 = 3x Divide by 3
x = -9 / 3
x = - 3

y = - x - 5
y = -(-3) - 5
y = - 2

So that point is where the two equations meet.

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and put this string in the question space.
y = -x - 5; y  = 2x + 4  Note the semi colon in the middle.

To the moderator: This is my own work. I'm using Wolfram to get the answer.

Idon’t know the answer to this

Aquadratic function is one of the form f(x)=ax2 + bx + c l, where a,b, and c are numbers with are not equal to zero.