Question

If a-b=0.9 ab=0.36
Find, 1. a+b
2. a^+b^

Answer 1

Answer:

1. .15 or -.15
2. 1.53

Step-by-step explanation:

$(a-b)^2=.9^2=.81$

$\implies a^2-2ab+b^2=.81$

$\implies a^2+b^2=.81+2ab=.81+.72=1.53$

and

$a^2+2ab+b^2=(a+b)^2=1.53+.72=2.25$

$\implies a+b=\pm \sqrt{2.25}=\pm .15$