Answer:
2. Both
3. e = 3, f = -5, g = 2
Step-by-step explanation:
2. Order doesn't affect product
3. You get e • f = -15, e • g = 6, f • g = -10 from the problem.
e = -15/f (solve for e)
(-15/f) • g = 6 (plug into second equation)
(-15g/f) = 6 (multiply)
-15g = 6f (multiply)
(-5g/2) = f (divide)
(-5g/2) • g = -10 (plug into last equation)
(-5g^2)/2 = -10 (multiply)
-5g^2 = -20 (mulitply)
g^2 = 4 (divide)
g = 2 (square root)
e • g = 6 (plug in for g, solve for e)
e • 2 = 6
e = 3
f • g = -10 (plug in for g, solve for f)
f • 2 = -10
f = -5
I don't know if your teacher made a typo because I tried this multiple times and got the same answer. I don't know how e is negative.
Radio Barn : 200 + .15 x x = the weekly sales
Woofer: 300 + .10x
set them equal to find when they are them same
200 + .15x = 300 + .10x
subtract .10x from both sides
200 +.15x -.10x = 300 + .10x-.10x
200 +.05x = 300
subtract 200 from each side
200+.05x -200 = 300-200
.05x = 100
divide each side by .05
.05x/.05 = 100/.05
x =2000
The 2 jobs pay the same when the weekly sales are 2000 dollars
2. {x - 5 = -y}
{2y - 10 = -2x}
x-5 = -y
add 5 to each side
x = -y+5
multiply each side by -2
-2x = 2y -10
the 2 equations are the same, it has an infinite number of solutions
The system is dependent since the 2 equations are the same line
3. {2x = y - 7}
{4x - 2y - 14 = 0}
2x = y-7
subtract y-7 from each side
2x - (y-7) = 0
2x -y+7 =0
multiply by 2
4x -2y +14 =0
subtract the two equations
4x -2y +14 =0
4x - 2y - 14 = 0
---------------------------
28 = 0
since this cannot happen the lines will never cross ( parallel lines)
the system is inconsistent