Question

What is the standard form of # y= (x + 9) (x + 6) #?

Answer 1

`y=x^2+15x+54`

Explanation:

A quadratic formula given by `a(bx+c)(dx+e), e!="Euler's number"` will have a standard form equal to:
`abdx^2+a(cd+eb)x+ace` (this is given by expanding out the brackets:

Here:
`a=1`
`b=1`
`c=9`
`d=1`
`e=6`

So:
`y=(1*1*1)x^2+1(1*9+1*6)x+1*9*6`
`y=x^2+15x+54`

To put it simply:
`y=x*x+9x+6x+9*6`
`y=x^2+15x+54`