Question

Help please please !!!!!!!

Answer 1

In each case, you can use the second equation to create an expression for y that will substitute into the first equation. Then you can write the result in standard form and use any of several means to find the number of solutions.

System A
  x² + (-x/2)² = 17
  x² = 17/(5/4) = 13.6
  x = ±√13.6 . . . . 2 real solutions

System B
  -6x +5 = x² -7x +10
  x² -x +5 = 0
The discriminant is ...
  D = (-1)²-4(1)(5) = -20 . . . . 0 real solutions

System C
  y = 8x +17 = -2x² +9
  2x² +8x +8 = 0
  2(x+2)² = 0
  x = -2 . . . . 1 real solution