+0  
 
0
43
3
avatar

Let a and b be real numbers such that a + b = -1.  Compute a^2 - b^2 + 2a.

 Jun 13, 2021
 #1
avatar+287 
0

The answer can be written out as an expression in terms of $a$ alone or $b$ alone.    You need to know either the value of $a$ or $b$ in order to know the exact value of $a^2-b^2+2a$.
 

 Jun 13, 2021
 #2
avatar+45 
0

\(a^2-b^2+2a\)

\(=(a+b)(a-b)+2a\)

\(=-1(a-b)+2a\)

\(=-a-(-b)+2a\)

\(=b-a+2a\)

\(=b+a\)

\(=-1\)

.
 Jun 15, 2021
 #3
avatar+287 
0

You're right.   I made an incorrect observation.

Bginner  Jun 19, 2021

10 Online Users

avatar