Question

Hello...can you please let me know if I worked this problem correctly:

10Z2^ + 8z - 7 = 16z2^ + 48z - 12

0 = 6z2^ + 30z - 5

a = 6
b = 30
c = -5

x = 30 + or - (30 2^ -4(6)(-5) / 12

x = -30 + 31.937 / 12 = .161

x = -30 - 31.937 / 12 -5.161

Am I on the right track?

Thank you

Answer 1

right track, but you made a mistake right at the start:

6z^2 + 40z - 5 = 0
z = (-40±√(40^2+4*6*5))/12
= (-40±√(1600-120))/12
= (-40±√1480)/12
= (-40±2√370)/12
= (-20±√370)/6

z = -0.127 or -6.539