Chapter 9 - Quadratic Functions and Equations - 9-8 Systems of Linear and Quadratic Equations - Practice and Problem-Solving Exercises - Page 585: 19

$x= 6, -9$

Blue line: $y=3x-20$ Red line: $y=-x^2+34$ $3x-20=-x^2+34$ $x^2+3x-54=0$ $x^2+9x-6x-54=0$ $x(x+9)-6(x+9)=0$ $(x+9)(x-6)=0$ $x+9=0$ $x=-9$ $x-6=0$ $x=6$ $x=-9$ $y=3x-20$ $y=3*(-9)-20$ $y=-27-20$ $y=-47$ $x=6$ $y=3x-20$ $y=3*6-20$ $y=18-20$ $y=-2$