I could use a hand, mathematic lads and legends

DMurphy33

New member
Joined
Oct 9, 2019
Messages
2
Yo, my class is retaking a maths test tomorrow. There’s one question I didn’t understand at all in the previous test, the teacher has yet to go through it, and I could use a hand. First time using a site like this so I hope I’m doing this right. Cheers lads

17x-5x2
 

Romsek

Full Member
Joined
Nov 16, 2013
Messages
396
I don't see any question.
 

Subhotosh Khan

Super Moderator
Staff member
Joined
Jun 18, 2007
Messages
19,081
Yo, my class is retaking a maths test tomorrow. There’s one question I didn’t understand at all in the previous test, the teacher has yet to go through it, and I could use a hand. First time using a site like this so I hope I’m doing this right. Cheers lads

17x-5x2
Do you mean lassies in this group are not invited to answer your query??
 

DMurphy33

New member
Joined
Oct 9, 2019
Messages
2
Do you mean lassies in this group are not invited to answer your query??
My friend, the lassies are the legends.
Sincerely, a girl attending a girls only secondary school
 

Subhotosh Khan

Super Moderator
Staff member
Joined
Jun 18, 2007
Messages
19,081
Yo, my class is retaking a maths test tomorrow. There’s one question I didn’t understand at all in the previous test, the teacher has yet to go through it, and I could use a hand. First time using a site like this so I hope I’m doing this right. Cheers lads

17x-5x2
You did not pose a question yet - just wrote a function of 'x'!!

What do you need to answer from that function?
 

pka

Elite Member
Joined
Jan 29, 2005
Messages
8,709
You posted in beginning algebra.
So we assume you are to solve the equation \(\displaystyle 17x-5x^2=0\)
\(\displaystyle 17x-5x^2=0\\x(17-5x)=0\\x=0\text{ or }x=\dfrac{17}{5}\)
If this is an incorrect reading then tell us what it is.
 

JeffM

Elite Member
Joined
Sep 14, 2012
Messages
3,935
To expand on pka's answer, if you have an equation of the form

\(\displaystyle g(x) * h(x) = 0 \implies g(x) = 0 \ne h(x) \text { or } h(x) = 0 \ne g(x) \text { or } g(x) = 0 = h(x).\)

This is called the zero-product property. Therefore

\(\displaystyle 17x - 5x^2 = 0 \implies x(17 - 5x) = 0 \implies\)

\(\displaystyle x = 0 \text { or } 17 - 5x = 0 \implies x = 0 \text { or } 5x = 17 \implies\)

\(\displaystyle x = 0 \text { or } x = \dfrac{17}{5}.\)
 
Top