# Math Help - Equation of absolute an absolute value function

1. ## Equation of absolute an absolute value function

Hello forum, Vaironxxrd here.
I missed a day school and some content in Algebra 2.

I'm required to make an equation using a given vertex and a given point.

Vertex = (0,1)
Crosses through(1,-2)

I would say the equation is y=2|x-0|+1
Is this wrong?

2. ## Re: Equation of absolute an absolute value function

Originally Posted by vaironxxrd
Hello forum, Vaironxxrd here.
I missed a day school and some content in Algebra 2.

I'm required to make an equation using a given vertex and a given point.

Vertex = (0,1)
Crosses through(1,-2)

I would say the equation is y=2|x-0|+1
Is this wrong?<--- yes
1. If you plug in the coordinates of the given point you'll get:

$-2=2 \cdot |1-0| + 1~\implies~-2 = 3$

This is true only if you are a banker.

2. Start with

$y=a \cdot |x-0| + 1$

plug in the coordinates and solve for a.