x(x+3)=1.75

Solution for x(x+3)=1.75 equation:

x(x+3)=1.75

We move all terms to the left:

x(x+3)-(1.75)=0

We add all the numbers together, and all the variables

x(x+3)-1.75=0

We multiply parentheses

x^2+3x-1.75=0

a = 1; b = 3; c = -1.75;
Δ = b2-4ac
Δ = 32-4·1·(-1.75)
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-4}{2*1}=\frac{-7}{2}
=-3+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+4}{2*1}=\frac{1}{2}
=1/2
$