Simultaneous equations are equations that involves two or more unknown variables. There must be as many equations as the number of unknown variables in order for us to solve the problem. There are two types of simultaneous equations, the first is liner and the second is mixed. For linear simultaneous equations, please refer to linear simultaneous equations.In this example, we will show you how to design a program that can solve mixed simultaneous equations, that is , one linear equation and one quadratic equation. The interface is as shown below:
Mixed simultaneous equations take the following forms:
ax+by=m
cx^{2}+dy^{2}=n
Simultaneous equations can normally be solved by the substitution or elimination methods. In this program, we employed the substitution method. So, we obtained the following formulas:
x1 = (m a d + Sqr(m ^{2} a ^{2} d ^{ 2}  (b ^{2} c + a ^{2} d) (d m ^{2}  b^{ 2 }n))) / (b ^{2} c + a ^{2} d)
x2 = (m a d +Sqr(m ^{2} a ^{2} d ^{ 2}  (b ^{2} c + a ^{2} d) (d m ^{2}  b^{ 2 }n))) / (b ^{2} c + a ^{2} d)
y1 = (m  a x1) / b
y2 = (m  a x2) / bTo limit the answers to two decimal places, we use the round function.
The Code
Private Sub Command1_Click() 

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