formulas...

[dgolverk]

given :a+b=8 ab=12

how much is:
a-b
a^2+b^2

1 + 1
a^2 b^2

You need use in these formulas:
(a+b)^2
(a-b)^2
(a-b)(a+b)

Thanks! I need it for a test tomorrow so please help me fast

 

[stapel]

You are given that a + b = 8 and ab = 12, and are asked (I think) to find a - b, a² + b², and 1/a² + 1/b².

How far have you gotten in finding the values of a and b? Or in using the various identities by substituting in the given values?

Thank you.

Eliz.

 

[dgolverk]

Thanks for replaying

I've already found the answer...
Now I'm stuck in another...
given:
a+b=7
a-b=5

how much is:

a^2+b^2

ab

 

[stapel]

This one is actually simpler than the previous one. Use similar techniques, or else solve directly for the values of a and b.

Eliz.

 

[Denis]

Re: Thanks for replaying

I've already found the answer...
Now I'm stuck in another...
given:
a+b=7
a-b=5

What do you get when you add those 2 equations together?