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Solve the following system of equations.

y = x - 1
x^2 + y^2 =25

A) (-3,-4) (4,3)

B) (4,3)

C) (-3,-4)

D) No solution

Respuesta :

The answer is option A

Once you try substituting the values of options B and C, the equation is equal on both left and right hand sides hence the solutions is A

Answer:

Option A

A) (-3,-4) (4,3)

Step-by-step explanation:

We have a system of equations composed of:

The equation of a circle that has center at point (0,0) and radius r = 5.

The equation of a line that intercepts the y-axis at point (0,1)

To solve the system we substitute the equation of the line in the equation of the circumference:

[tex]y = x - 1\\\\x ^ 2 + y ^ 2 = 25[/tex]

Then

[tex]x ^ 2 + (x-1) ^ 2 = 25[/tex]

We solve for x.

[tex]x ^ 2 + x ^ 2 -2x +1 = 25\\\\2x ^ 2 -2x -24 = 0[/tex]

We divide by 2 both sides of the equation

[tex]x^2 -x -12 = 0[/tex]

We look for two numbers that multiply as a result -12 and that add them as a result -1.

These numbers are -4 and 3.

Therefore the factors are:

[tex](x-4) (x + 3) = 0[/tex]

Finally the solutions are:

[tex]x = 4[/tex] and [tex]x = -3[/tex]

The ordered pairs are:

(-3,-4) (4,3)