Answer:
Step-by-step explanation:
1. x^2-x-20=3x-15
x=5, x=1 substitute
y=3*5-15 = 0
y=3*(-1)-15 = -18
Solution: (5,0) & (-1,-18)
2. x^2+2x+3=x+5
x=-2, x=1 substitute
y= -2+5 = 3
y=1+5 = 6
Solution: (-2,3) & (1,6)