SOLUTION: Please solve and show work: 7/4 + 2/3 y^2 = 13y/6

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Question 776677: Please solve and show work:
7/4 + 2/3 y^2 = 13y/6
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
7%2F4+%2B+%282%2F3+%29y%5E2+=+%2813%2F6%29y
LCM of the denominators is 12. so multiply equation by 12
%287%2A12%29%2F4+%2B+%282%2A12%29%2F3+%29y%5E2+=+%2813%2A12%29%2F6%29y

21+8y^2=26y
8y^2-26y+21=0
Find the roots of the equation by quadratic formula
iiiii
a= 8 , b= -26 , c= 21

b^2-4ac= 676 + -672
b^2-4ac= 4
%09sqrt%28%094%09%29=%092%09
y=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
y1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29
y1=( 26 + 2 )/ 16
y1= 1.75
y2=%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29
y2=( 26 -2 ) / 16
y2= 1.50
y= 1.75 & 1.50