Question 712217
((4x)/(-5x+13))>=20 cross multiply
4x>=20(-5x+13)
4x>=-100x+260
4x+100x>=260
104x>=260
x>=260/104
x>=2.5 ans.
proof:
let x=2.5
((4*2.5)/(-5*2.5+13)>=20
((10)/(-12.5+13)>=20
10/.5=20
20=20