b*b+4.5b-17=0

Solution for b*b+4.5b-17=0 equation:

b*b+4.5b-17=0

We add all the numbers together, and all the variables

4.5b+b*b-17=0

Wy multiply elements

b^2+4.5b-17=0

a = 1; b = 4.5; c = -17;
Δ = b2-4ac
Δ = 4.52-4·1·(-17)
Δ = 88.25
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(4.5)-\sqrt{88.25}}{2*1}=\frac{-4.5-\sqrt{88.25}}{2}
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4.5)+\sqrt{88.25}}{2*1}=\frac{-4.5+\sqrt{88.25}}{2}
$