Answer:
3x^2 + 7x - 5 + 2x^2
= 5x^2 + 7x - 5 (a=5, b=7, c=-5)
x = (-b+/- √(b^2 - 4ac))/2a
= (-7+/- √(49+100))/10
= (-7+√149)/10, (-7-√149)/10
Hope this helps!