Question

What is the solution to the system of inequalities:

x – 2y > –16
3x + 4y < 20

Answer 1

Sketch the graph of each line in the plane;
x-2y=-16 has intercepts (0,8) and (-16, 0) and you would shade below the line
3x+4y=20 has intercepts (0,5) and (20/3, 0) and you would shade below the line
I made an error with the sketch; gimme a minute to do it again)

Answer 2

here is the sketch

Answer 3

x-2y>-16 so x=2y-16 plug this x in for second equation
3(2y-16)+4y<20 now solve this for y
10y-48<20 so y is 68/10=34/5 now solve for x using x=2y-16
x=2(34/5)-16=(66/5)-16=-14/5 so the solution to these is the point
(-14/5,34/5)

Answer 4

thts not one of the choices..
the choices are
(8, 3)
(11, –1)
(–4, –6)
(–2, 7)

Answer 5

I really need help..thank you soo much you guyzz

Answer 6

hey katrina

Answer 7

Hello :)

Answer 8

MeEngr, thnks for the help...but are you sure thats the right answer??

Answer 9

u know...you can work backwards and check if any of the choices make the question true...so for example...for x=8 y=3 plug in the system and check if they are true so 2>-16 and 36<20 no thats not true so choice number one is not right...move on to next one x=11 y=-1 so 13>-16 and 29<20 so thats not right..next one x=-4 y=-6 so 8>-16 and -36<20 so thats true..last one x=-1 y=7 so 13>-15 and 25<20 not true so only solution true is (-4,-6) because it satisfies the inequalities now