Question 86115
[(2X-6)/21]/[(5X-15)/12] TO SIMPLIFY THIS PROCESS WE NEED TO INVERT THE DENOMINATOR AND THEN MULTIPLY.
[(2X-6)/21]*[12/(5X-15)]
(2X-6)(5X-15)=12*21
10X^2-30X-30X+90=252
10X^2-60X+90-252=0
10X^2-60X-162=0
TO SOLVE THIS EQUATION WE NEED TO USE THE QUADRATIC EQUATION.
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
X=(60+-SQRT[-60^2-4*10*-162])/2*10
X=(60+-SQRT[3600+6480])/20
X=(60+-SQRT10080)/20
X=(60+-100.4)/20
X=(60+100.4)/20
X=160.4/20
X=8.02 ANSWER.
X=(60-100.4)/20
X=-40.4/20
X=-2.02 ANSWER.