Solve the system by using the substitution method

Question

1. 2x+y=5

        x²+y²=50

 

 

     2. x²+y²=90

         y=√x

 

Answer 1

1)

 

Substitute the first equation into the circle equation.  From the first equation,

 

y = -2x + 5

 

x² + (-2x + 5)² = 50

 

Solve for x from this equation.  You will have two values of x.

 

 

2)

 

Substitute the second equation into the circle equation.  From the second equation,

 

y = √x   --->   y² = x

 

 

Then

 

x² + x = 90

 

Solve for x from this equation.