mlb298
contestada

ill give brainliest and 5 stars and thanks if answer this what is the result of substituting for y in the bottom equation

y=x+3

y=x^2+2x-4

Respuesta :

We have two set of solutions , (  [tex]\frac{\sqrt{29} }{2}[/tex]  ,  [tex]\frac{\sqrt{29} }{2}[/tex] + 3 ) , (  -[tex]\frac{\sqrt{29} }{2}[/tex] + 3 ,  -[tex]\frac{\sqrt{29} }{2}[/tex] + 3).

Step-by-step explanation:

We have , the following equations:

[tex]y = x+3[/tex]  and [tex]y = x^{2} +2x -4[/tex] . Let's substitute value of y in bottom equation:

⇒ [tex]y = x^{2} +2x -4[/tex]

⇒ [tex]x+3 = x^{2} +2x -4[/tex]

⇒ [tex]x^{2} +x -7= 0[/tex]

Roots of quadratic equation are given by: a = 1, b= 1 , c = -7

[tex]x = \frac{\sqrt{b^{2}-4ac} }{2a}[/tex]

⇒ [tex]x = \frac{\sqrt{b^{2}-4ac} }{2a}[/tex]

⇒ [tex]x = \frac{\sqrt{1^{2}-4(1)(-7)} }{2(1)}[/tex]

⇒ [tex]x = \frac{\sqrt{29} }{2}[/tex] which is actually x = ± [tex]\frac{\sqrt{29} }{2}[/tex] .

We know that [tex]y = x+3[/tex],

⇒ y = ± [tex]\frac{\sqrt{29} }{2}[/tex] + 3.

We have two set of solutions , (  [tex]\frac{\sqrt{29} }{2}[/tex]  ,  [tex]\frac{\sqrt{29} }{2}[/tex] + 3 ) , (  -[tex]\frac{\sqrt{29} }{2}[/tex] + 3 ,  -[tex]\frac{\sqrt{29} }{2}[/tex] + 3).