Respuesta :
All the equations have 2 real roots or solutions except for equation 4 which have only one real root.
To find the number of real solutions the quadratic equation have, we would use quadratic formula to do this.
[tex]x = \frac{-b +- \sqrt{b^2 -4ac} }{2a}[/tex]
First Equation,
data given;
- a = 12
- b = -9
- c = 4
substitute it into the formula
[tex]\frac{-(-9)+-\sqrt{(-9)^2 - 4(12)(4)} }{2(12)}\\\frac{9 +- 16.52 }{24}\\x = 1.063 or x = -0.313[/tex]
Second Equation
data given
[tex]10x+y = -x^2 +2\\y = -x^2-10x+2\\y = x^2 +10x-2\\[/tex]
- a = 1
- b = 10
- c = -2
substitute the values into the equation
[tex]\frac{-b +- \sqrt{b^2 -4ac } }{2a} \\\frac{-10+- \sqrt{10^2 -4*1*-2} }{2*1} \\x = 0.195 or x = -10.195[/tex]
Third Equation
data given;
[tex]4y - 7 = 5x^2 - x+ 2 +3y\\4y -3y = 5x^2-x +2 - 7\\y = 5x^2 - x -5[/tex]
- a = 5
- b = -1
- c = - 5
[tex]\frac{-(-1)+- \sqrt{(-1)^2-4(5)(-5)} }{2(5)} \\x = 0.905 or x = - 0.55[/tex]
Fourth Equation
[tex]y = (-x + 4)^2\\y = x^2 +2(-4x)+16\\y = x^2 -8x + 16[/tex]
- a = 1
- b = -8
- c = 16
substitute into the equation and solve
[tex]\frac{-b+-\sqrt{b^2 - 4ac} }{2a} \\x = \frac{-(-8)+- \sqrt{(-8)^2 -4(1)(16)} }{2(1)}\\x = 8/2 \\x = 4[/tex]
from the calculations above, all the equation have two real roots except for the last one which have only one real root.
Learn more about quadratic roots here;
https://brainly.com/question/1214333