How do you solve #15x^2=7x+2#?

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Answer 1 · 2018-05-28T18:13:10

#x_1=-1/5# and #x_2=2/3#

#15x^2=7x+2#

#15x^2-7x-2=0#

#15x^2-10x+3x-2=0#

#5x*(3x-2)+3x-2=0#

#(3x-2)*(5x+1)=0#

So #x_1=-1/5# and #x_2=2/3#

Answer 2 · 2018-05-28T18:24:20

#x_1=2/3# or #x_2=-1/5#

Dividing by #15# we get
#x^2-7/15x-2/15=0#
#x_{1,2}=7/20pmsqrt(49/300+2/15)#
#x_{1,2}=7/30pm13/30#
#x_1=2/3#
#x_2=-1/5#