Answer:
(x-5) (x+4)
Step-by-step explanation:
x^2 -x -20
What two terms multiply to -20 and add to -1
-5*4 = -20
-5+4 = -1
(x-5) (x+4)
Hiya. I'm going to rewrite the second equation.
By subtracting 5x by both sides, I'll be able to have y by itself:
-y=-5x+13
I'm going to then divide both sides by -1 to get:
y=5x-13.
Then, I'm going to plug that equation into the first equation
3x+2(5x-13)=39
Factor:
3x+10x-26=39
Combine like terms:
13x=65
Divide both sides by 13 to get x by itself to get x=5
Plug this back into the equation of y=5x-13
y=5(5)-13 to get y=12
The rate of change in z at (4,9) as we change x but hold y fixed is =
3/[2sqrt(3x+2y)] put x = 4 , y = 9 = 3/[2sqrt(12+18) = 3/[2sqrt(30)] The
rate of change in z at (4,9) as we change y but hold x fixed is =
1/sqrt(3x+2y) put x = 4, y =9 = 1/sqrt(30)