# ACT Math 3.4 Elementary Algebra

ACT Math Elementary Algebra Drill 3, Problem 4. Solve for y in this equation.

ACT Math | Elementary Algebra |

ACT Mathematics | Elementary Algebra |

Algebra | Understand the relationship between zeros and factors of polynomials Use polynomial identities to solve problem Use polynomial identities to solve problems |

Elementary Algebra | Solve quadratic equations by factoring Solving simple quadratic equations |

Foreign Language | Arabic Subtitled Chinese Subtitled Korean Subtitled Spanish Subtitled |

Language | English Language |

Polynomials | Factoring Polynomials |

Product Type | ACT Math |

### Transcript

We just have to figure out what the factors are... and there's a bit of a curveball in

here in that there's a 2 on the front end.

So we know that one of the factors is going to be a 2, as in:

The quantity 2y plus something times the quantity y plus something.

Let's plug in some numbers to get the 3. It's kind of easy because 3 only has 2 factors:

1 and 3...

Now we have quantity 2y plus 1 times quantity y plus 3.

If we multiply it out, we get 2y times y here, which is 2y squared.

Then we have 2y times 3, which is 6y

plus y times 1, which is just... y.

6y plus y is 7y; then, 1 times 3 is just 3 so we're done.

But now... how do we make the whole thing equal to zero? Well, one of the elements here

has to BE zero.

If y is negative 3 then this one is 3 minus 3 which is 0...

...and here, it's just negative one half, because negative 1 half times 2 is negative

1... and negative 1 plus positive 1 is zero.

So the other answer is negative one half and the answer is A and C...

...or option E.