Question

How do you find the missing number or term to make a perfect square trinomial. `y^2 + 0.1y +___`?

Answer 1

I found: `y^2+0.1y+(0.05)^2=y^2+0.1y+0.0025`

Explanation:

I would write it as:
`y^2+1/10y+....`
the missng number must be such that multiplied by `2` gives `1/10`;
it could be `1/20`; so the complete trinomial could be:
`y^2+1/10y+1/(20)^2=(y+1/20)^2`
in decimal form:
`y^2+0.1y+(0.05)^2=y^2+0.1y+0.0025`