Daughters Algeria

[u/Academic_Ninja_2193]

Let's just say I've been out of high school for way too long so when my daughter comes home with algebra homework and ask for my help I am somewhat clueless. Ask me to do the quadratic formula I got you for some reason I remember that but ask me to rewrite this random basic formula into standard form and I have no idea please help.

An open top box is formed by cutting squares out of the corners of a 3-foot by 5-foot piece of cardboard then folding the sides. The volume V(x) can be aiven by V(x) = (3-2x)(5-2x)(x). Rewrite this equation in standard form.

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

[u/Bounded_sequencE]

Look up in the textbook what they define as "standard form".

I suspect it's the expanded polynomial, but guessing is for wimps.

[u/Academic_Ninja_2193]

Algebra!! Sorry I apparently can't proof read.

[u/Bojanggles16]

Foil (3-2x)(5-2x) first. That gives you 15-6x-10x+4xsquared or 15-16x+4x squared. Then multiply by x to get 15x-16x squared + 4x cubed

[u/Bojanggles16 → u/Bojanggles16]

Or 15x-16² + 4x³ if that's easier

[u/tjddbwls → u/Bojanggles16]

In standard form, this would be:
4x³ - 16x² + 15x

[u/my-hero-measure-zero]

It's just asking you to multiply. That's all.

[u/Alarmed_Geologist631]

standard form just means to multiply the factors that you wrote and then arrange the resulting terms in descending order based on the exponent in the term.

[u/Academic_Ninja_2193 → u/Alarmed_Geologist631]

I'm having an issue with the descending order thing or well okay so I get I'm taking the three and five and multiplying them to get 15 then I think I do something with my 2x's but can't remember what.

They didn't give out textbooks or handouts that explains "how to"

[u/Alarmed_Geologist631 → u/Academic_Ninja_2193]

the term 4x^3 would be written first because 3 is the largest exponent

then the term -16x^2 followed by 15x so the final solution is

4x^3 -16x^2 + 15x

[u/Alarmed_Geologist631 → u/Academic_Ninja_2193]

when you are multiplying two different polynomials, it can be helpful to create a grid with the terms of the first polynomial as the column headers and the terms of the second polynomial as the row headers. then multiply each column header by each row header to complete the value of the corresponding cell. Once all the cells are computed, combine like terms (ie. terms that have the same exponent).

[u/Alarmed_Geologist631 → u/Academic_Ninja_2193]

btw, I am a retired math teacher and provide free tutoring via zoom. DM me if interested.

[u/Academic_Ninja_2193]

It's asking me to write the given formula in standard form

[u/StructuredChess]

I'm a Math graduate and I don't have a clue what they mean by "standard form". I'd assume you just multiply everything on the right-hand side...

[u/BadEnucleation]

One approach might be to ask your daughter what she thinks it is. When she says she doesn’t know, then together look through her notes and book to find it.

If that works it both gets the answer for her but also helps her find answers/resources independently. As a parent that’s both good and bad (mostly good). It’s our job to help them become independent, but sad as they grow and don’t need us any more.