Question

Solve the inequality
x 15
--- + ---- <= 4
4 x+7

for domain

Answer 1

x cant be -7 so we can rule any option that includes that...

Answer 2

we can get like denoms again; that worked prety well last time :)

x^2 +7x + 60 <= 16x +16(17)

x^2 -9x +60 - 16(17) <= 0 ..... 142 + 60 + 70 = 272 - 60 = -212

x^2 -9x -212 <=0

Answer 3

9/2 +- sqrt(81 -4(-212))/2

9/2 +- sqrt(929)/2..oh you picked a doozey eh...

Answer 4

whats your options?

Answer 5

x^2 +7x + 60 <= 16x +16(17)

x^2 -9x +60 - 16(7) <= 0 ..... 70+42 = 112 - 60 = 52

x^2 -9x -52 <=0 is better

9/2 +- sqrt(81+108)/2

9/2 +- sqrt(189)/2

[ 9 (+-) 3sqrt(21) ]/2