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2 votes
9z(7z-4)=6 step by step please

User Zmart
by
9.2k points

2 Answers

5 votes
Expand 9z(7z - 4): 63z^2 - 36z
63z^2 - 36z = 6
Subtract 6 from both sides
63z^2 - 36z - 6 = 6 - 6
Simplify
63z^2 - 36z - 6 = 0
z= 6 + radicant 78/ 21, z= 6- radicant 78/ 21
User Wholerabbit
by
8.4k points
4 votes
Distribute 9z to 7z and -4
You get 56z^2 - 36z = 6
56^2 - 36 - 6 = 0
Solve using quadratic formula
z is approx 0.78 and approx. -0.14
User Makelc
by
8.7k points